# Relationship history for MSHA mine 1509317

Current hierarchy: **Michael K  Cook; Randy A  Cook → Cesco Coal Company Inc → No 1 Surface**

- 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:** Cesco Coal Company Inc → No 1 Surface; 1975-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Michael K  Cook et al → No 1 Surface; 1975-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael K  Cook et al → Cesco Coal Company Inc; 1975-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Randy A  Cook et al → Cesco Coal Company Inc; 1975-10-01 to current/open; source msha-controller-operator-history