# Relationship history for MSHA mine 1102722

Current hierarchy: **E M Melahn Construction Company Inc → Road Materials Corp → Dundee North**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** E M Melahn Construction Company Inc → Dundee North; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Road Materials Corp → Dundee North; 1980-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** E M Melahn Construction Company Inc → Road Materials Corp; 1980-01-01 to current/open; source msha-controller-operator-history