# Relationship history for MSHA mine 0502660

Current hierarchy: **Energy Fuels Coal Resources Ltd → Kerr Coal Corp → Kerr 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:** Kerr Coal Company → Kerr Tipple; 1974-11-01 to 1977-10-18; source msha-controller-operator-history
- **controller_controls_mine:** Kerr W M → Kerr Tipple; 1974-11-01 to 1977-10-18; source msha-controller-operator-history
- **controller_controls_operator:** Kerr W M → Kerr Coal Company; 1974-11-01 to 1977-10-18; source msha-controller-operator-history
- **controller_controls_mine:** Energy Fuels Coal Resources Ltd → Kerr Tipple; 1977-10-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Kerr Coal Corp → Kerr Tipple; 1977-10-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Energy Fuels Coal Resources Ltd → Kerr Coal Corp; 1977-10-19 to current/open; source msha-controller-operator-history