# Relationship history for MSHA mine 4201637

Current hierarchy: **El Paso Energy Corp → Coastal States Energy Company → Levan Unit Train Loadout Facility**

- 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:** Coastal States Energy Company → Levan Unit Train Loadout Facility; 1979-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** El Paso Energy Corp → Levan Unit Train Loadout Facility; 1979-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** El Paso Energy Corp → Coastal States Energy Company; 1979-12-01 to current/open; source msha-controller-operator-history