# Relationship history for MSHA mine 0301135

Current hierarchy: **Jones Harold → Delight Sand & Gravel → Delight Pit & Plant**

- 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:** Prescott Sand & Gravel → Delight Pit & Plant; 1950-01-01 to 1982-12-01; source msha-controller-operator-history
- **controller_controls_mine:** Andrews Robert → Delight Pit & Plant; 1950-01-01 to 1982-12-01; source msha-controller-operator-history
- **controller_controls_operator:** Andrews Robert → Prescott Sand & Gravel; 1950-01-01 to 1982-12-01; source msha-controller-operator-history
- **operator_operates_mine:** Delight Sand & Gravel → Delight Pit & Plant; 1982-12-02 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jones Harold → Delight Pit & Plant; 1982-12-02 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jones Harold → Delight Sand & Gravel; 1982-12-02 to current/open; source msha-controller-operator-history