# Relationship history for MSHA mine 0400213

Current hierarchy: **Vicat S A → NATIONAL CEMENT COMPANY OF CALIFORNIA INC → LEBEC CEMENT 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

- **operator_operates_mine:** General Portland Inc → LEBEC CEMENT PLANT; 1950-01-01 to 1981-11-11; source msha-controller-operator-history
- **controller_controls_mine:** General Portland Inc → LEBEC CEMENT PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** General Portland Inc → General Portland Inc; 1950-01-01 to 1981-11-11; source msha-controller-operator-history
- **operator_operates_mine:** General Portland Inc → LEBEC CEMENT PLANT; 1981-11-12 to 1987-11-11; source msha-controller-operator-history
- **controller_controls_mine:** Lafarge S A → LEBEC CEMENT PLANT; 1981-11-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lafarge S A → General Portland Inc; 1981-11-12 to 1987-11-11; source msha-controller-operator-history
- **operator_operates_mine:** National Cement Company Of California Inc → LEBEC CEMENT PLANT; 1987-11-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Vicat S A → LEBEC CEMENT PLANT; 1987-11-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Vicat S A → National Cement Company Of California Inc; 1987-11-12 to current/open; source msha-controller-operator-history