# Relationship history for MSHA mine 1515163

Current hierarchy: **Cindy A  Stewart → Savannah Coal Inc → No 1**

- 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

- **operator_operates_mine:** O J Construction Company Inc → No 1; 1985-04-01 to 1986-09-09; source msha-controller-operator-history
- **controller_controls_mine:** Blackburn Freddie Iii → No 1; 1985-04-01 to 1986-09-09; source msha-controller-operator-history
- **controller_controls_operator:** Blackburn Freddie Iii → O J Construction Company Inc; 1985-04-01 to 1986-09-09; source msha-controller-operator-history
- **operator_operates_mine:** Savannah Coal Inc → No 1; 1986-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cindy A  Stewart → No 1; 1986-09-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cindy A  Stewart → Savannah Coal Inc; 1986-09-10 to current/open; source msha-controller-operator-history