# Relationship history for MSHA mine 4603748

Current hierarchy: **Hanna Michael → Hanna & Solomon Coal Company Inc → #2 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:** Cadco Coal → #2 Surface; 1950-01-01 to 1974-02-20; source msha-controller-operator-history
- **controller_controls_mine:** Cadco Coal → #2 Surface; 1950-01-01 to 1974-02-20; source msha-controller-operator-history
- **controller_controls_operator:** Cadco Coal → Cadco Coal; 1950-01-01 to 1974-02-20; source msha-controller-operator-history
- **operator_operates_mine:** C J Langenfelder & Son Inc → #2 Surface; 1974-02-21 to 1979-05-20; source msha-controller-operator-history
- **controller_controls_mine:** Scheeler Charles → #2 Surface; 1974-02-21 to 1979-05-20; source msha-controller-operator-history
- **controller_controls_operator:** Scheeler Charles → C J Langenfelder & Son Inc; 1974-02-21 to 1979-05-20; source msha-controller-operator-history
- **controller_controls_mine:** Hanna Michael → #2 Surface; 1979-05-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hanna & Solomon Coal Company Inc → #2 Surface; 1979-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanna Michael → Hanna & Solomon Coal Company Inc; 1979-05-21 to current/open; source msha-controller-operator-history