# Relationship history for MSHA mine 4800591

Current hierarchy: **Dana L  Sims → Modern Mining & Milling Inc → 3 Ms West Inc Blue Spar No 2 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Modern Mining & Milling Inc → 3 Ms West Inc Blue Spar No 2 Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dana L  Sims → 3 Ms West Inc Blue Spar No 2 Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dana L  Sims → Modern Mining & Milling Inc; 1950-01-01 to current/open; source msha-controller-operator-history