# Relationship history for MSHA mine 4201435

Current hierarchy: **Wolverine Fuels LLC → Canyon Fuel Company Llc → Skyline Mine No 1**

- 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

- **controller_controls_mine:** El Paso Energy Corp → Skyline Mine No 1; 1979-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Utah Fuel Company → Skyline Mine No 1; 1979-05-01 to 1996-12-19; source msha-controller-operator-history
- **controller_controls_operator:** El Paso Energy Corp → Utah Fuel Company; 1979-05-01 to 1996-12-19; source msha-controller-operator-history
- **operator_operates_mine:** Canyon Fuel Company Llc → Skyline Mine No 1; 1996-12-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Arch Resources Inc → Skyline Mine No 1; 1996-12-20 to 2013-08-16; source msha-controller-operator-history
- **controller_controls_operator:** Arch Resources Inc → Canyon Fuel Company Llc; 1996-12-20 to 2013-08-16; source msha-controller-operator-history
- **controller_controls_mine:** Wolverine Fuels LLC → Skyline Mine No 1; 2013-08-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wolverine Fuels LLC → Canyon Fuel Company Llc; 2013-08-17 to current/open; source msha-controller-operator-history