# Relationship history for MSHA mine 2600722

Current hierarchy: **Blasco Joseph Jr → Arrow Ready Mix Concrete → Arrow Ready Mix Pit And Mill**

- 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:** Arrow Ready Mix Concrete → Arrow Ready Mix Pit And Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Blasco Joseph Jr Et Al → Arrow Ready Mix Pit And Mill; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Blasco Joseph Jr Et Al → Arrow Ready Mix Concrete; 1950-01-01 to current/open; source msha-controller-operator-history