# Relationship history for MSHA mine 1510971

Current hierarchy: **Craft Buell → C & E 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:** C & E Coal Company → No 1 Surface; 1977-12-01 to 1979-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Watts Elmine → No 1 Surface; 1977-12-01 to 1979-01-31; source msha-controller-operator-history
- **controller_controls_operator:** Watts Elmine → C & E Coal Company; 1977-12-01 to 1979-01-31; source msha-controller-operator-history
- **operator_operates_mine:** C & E Coal Company Inc → No 1 Surface; 1979-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Craft Buell → No 1 Surface; 1979-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Craft Buell → C & E Coal Company Inc; 1979-02-01 to current/open; source msha-controller-operator-history