# Relationship history for MSHA mine 1509378

Current hierarchy: **Carl  Kirk → Amber Coal Company Inc → County Line Tipple**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** County Line Coal Company → County Line Tipple; 1975-09-01 to 1978-05-16; source msha-controller-operator-history
- **controller_controls_mine:** Barnett Bernard H → County Line Tipple; 1975-09-01 to 1978-05-16; source msha-controller-operator-history
- **controller_controls_operator:** Barnett Bernard H → County Line Coal Company; 1975-09-01 to 1978-05-16; source msha-controller-operator-history
- **controller_controls_mine:** Carl  Kirk et al → County Line Tipple; 1975-11-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Continental Resources & Mineral Corp → County Line Tipple; 1977-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Continental Coal Sales Corp → County Line Tipple; 1978-05-17 to 1983-12-15; source msha-controller-operator-history
- **controller_controls_operator:** Continental Resources & Mineral Corp → Continental Coal Sales Corp; 1978-05-17 to 1983-12-15; source msha-controller-operator-history
- **operator_operates_mine:** Amber Coal Company Inc → County Line Tipple; 1983-12-16 to 1985-06-12; source msha-controller-operator-history
- **controller_controls_operator:** Carl  Kirk et al → Amber Coal Company Inc; 1983-12-16 to 1985-06-12; source msha-controller-operator-history
- **operator_operates_mine:** County Line Fuel Inc → County Line Tipple; 1985-06-13 to 1987-08-25; source msha-controller-operator-history
- **controller_controls_mine:** Andrew J  Leckie → County Line Tipple; 1985-06-13 to 1987-08-25; source msha-controller-operator-history
- **controller_controls_operator:** Andrew J  Leckie → County Line Fuel Inc; 1985-06-13 to 1987-08-25; source msha-controller-operator-history
- **operator_operates_mine:** Amber Coal Company Inc → County Line Tipple; 1987-08-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carl  Kirk et al → Amber Coal Company Inc; 1987-08-26 to current/open; source msha-controller-operator-history