# Relationship history for MSHA mine 4102492

Current hierarchy: **Usx Corp & Nm Uranium Inc → Usx Corp/Tx Uranium Operation → Clay West Uranium Plant**

- 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:** United States Steel Corp → Clay West Uranium Plant; 1950-01-01 to 1985-06-30; source msha-controller-operator-history
- **controller_controls_mine:** USX Corp (United States Steel Corp) → Clay West Uranium Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** USX Corp (United States Steel Corp) → United States Steel Corp; 1950-01-01 to 1985-06-30; source msha-controller-operator-history
- **operator_operates_mine:** Usx Corp/Tx Uranium Operation → Clay West Uranium Plant; 1985-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Usx Corp & Nm Uranium Inc → Clay West Uranium Plant; 1985-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Usx Corp & Nm Uranium Inc → Usx Corp/Tx Uranium Operation; 1985-07-01 to current/open; source msha-controller-operator-history