# Relationship history for MSHA mine 4105639

Current hierarchy: **Lubbock County-TX → Lubbock County → Lubbock County Kahlich 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Lubbock County-TX → Lubbock County Kahlich Plant; 2021-07-28 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Lubbock County → Lubbock County Kahlich Plant; 2022-08-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lubbock County-TX → Lubbock County; 2022-08-23 to current/open; source msha-controller-operator-history