# Relationship history for MSHA mine 4202109

Current hierarchy: **Joe C  Chandler → Intermountain Excavating → Wood's 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** U S Aggregate Inc → Wood's Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Valley Asphalt Inc → Wood's Pit; 1994-08-01 to 2003-02-07; source msha-controller-operator-history
- **controller_controls_operator:** U S Aggregate Inc → Valley Asphalt Inc; 1994-08-01 to 2003-02-07; source msha-controller-operator-history
- **operator_operates_mine:** Intermountain Excavating → Wood's Pit; 2003-02-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joe C  Chandler → Wood's Pit; 2003-02-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joe C  Chandler → Intermountain Excavating; 2003-02-08 to current/open; source msha-controller-operator-history