# Relationship history for MSHA mine 0403031

Current hierarchy: **Taiheiyo Cement Corp → CALPORTLAND CONSTRUCTION → GAREY ROCK 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:** Union Asphalt Inc → GAREY ROCK PLANT; 1950-01-01 to 2008-03-26; source msha-controller-operator-history
- **controller_controls_mine:** Steven F  Will Et Al → GAREY ROCK PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steven F  Will Et Al → Union Asphalt Inc; 1950-01-01 to 2008-03-26; source msha-controller-operator-history
- **controller_controls_operator:** Andy C  Hermreck Et Al → Union Asphalt Inc; 1950-01-01 to 2008-03-26; source msha-controller-operator-history
- **controller_controls_mine:** Taiheiyo Cement Corp → GAREY ROCK PLANT; 1990-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** CALPORTLAND CONSTRUCTION → GAREY ROCK PLANT; 2008-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Taiheiyo Cement Corp → CALPORTLAND CONSTRUCTION; 2008-03-27 to current/open; source msha-controller-operator-history