# Relationship history for MSHA mine 2400483

Current hierarchy: **Rodd J  Farrow → Pioneer Concrete & Fuel Inc → Pioneer Concrete-Spangler 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:** Perfect Concrete → Pioneer Concrete-Spangler Pit; 1950-01-01 to 2006-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Rodd J  Farrow → Pioneer Concrete-Spangler Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rodd J  Farrow → Perfect Concrete; 1950-01-01 to 2006-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Pioneer Concrete & Fuel Inc → Pioneer Concrete-Spangler Pit; 2006-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Rodd J  Farrow → Pioneer Concrete-Spangler Pit; 2006-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rodd J  Farrow → Pioneer Concrete & Fuel Inc; 2006-09-01 to current/open; source msha-controller-operator-history