# Relationship history for MSHA mine 1510327

Current hierarchy: **Cotton Ben → Cotton Equipment 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:** Cedar Mining Company Inc → No 1 Surface; 1977-03-01 to 1978-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Holsclaw J Douglas → No 1 Surface; 1977-03-01 to 1978-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Holsclaw J Douglas → Cedar Mining Company Inc; 1977-03-01 to 1978-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Kemi Coal Company Inc → No 1 Surface; 1978-02-01 to 1978-07-25; source msha-controller-operator-history
- **controller_controls_mine:** Bailey John P → No 1 Surface; 1978-02-01 to 1978-07-25; source msha-controller-operator-history
- **controller_controls_operator:** Bailey John P → Kemi Coal Company Inc; 1978-02-01 to 1978-07-25; source msha-controller-operator-history
- **operator_operates_mine:** Cotton Equipment Company Inc → No 1 Surface; 1978-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cotton Ben → No 1 Surface; 1978-07-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cotton Ben → Cotton Equipment Company Inc; 1978-07-26 to current/open; source msha-controller-operator-history