# Relationship history for MSHA mine 1511020

Current hierarchy: **Combs Edison & H B Caudill → C & C Coal Company → No 1 Surface/Underground**

- 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:** C & C Coal Company → No 1 Surface/Underground; 1977-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Combs Edison & H B Caudill Et Al → No 1 Surface/Underground; 1977-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Combs Edison & H B Caudill Et Al → C & C Coal Company; 1977-11-01 to current/open; source msha-controller-operator-history