# Relationship history for MSHA mine 1511493

Current hierarchy: **David  Reeves → Albany Redi-Mix Inc → Bald Rock Sand**

- 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

- **controller_controls_mine:** Lena  Pritchard → Bald Rock Sand; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bald Rock Sand Company Inc → Bald Rock Sand; 1978-03-09 to 1990-02-04; source msha-controller-operator-history
- **controller_controls_operator:** Lena  Pritchard → Bald Rock Sand Company Inc; 1978-03-09 to 1990-02-04; source msha-controller-operator-history
- **operator_operates_mine:** Bald Rock Sand Company Inc → Bald Rock Sand; 1990-02-05 to 1992-06-15; source msha-controller-operator-history
- **controller_controls_mine:** Charles  Crabtree → Bald Rock Sand; 1990-02-05 to 1992-06-15; source msha-controller-operator-history
- **controller_controls_operator:** Charles  Crabtree → Bald Rock Sand Company Inc; 1990-02-05 to 1992-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Albany Redi-Mix Inc → Bald Rock Sand; 1992-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** David  Reeves → Bald Rock Sand; 1992-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David  Reeves → Albany Redi-Mix Inc; 1992-06-16 to current/open; source msha-controller-operator-history