# Relationship history for MSHA mine 0404150

Current hierarchy: **Hanson PLC → Livingston Graham/Blue Diamond Materials → Fontana 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:** Fontana Paving Inc → Fontana Plant; 1950-01-01 to 1988-06-09; source msha-controller-operator-history
- **controller_controls_mine:** Sprinkel Warren Reed → Fontana Plant; 1950-01-01 to 1988-06-09; source msha-controller-operator-history
- **controller_controls_operator:** Sprinkel Warren Reed → Fontana Paving Inc; 1950-01-01 to 1988-06-09; source msha-controller-operator-history
- **controller_controls_mine:** Boral Limited → Fontana Plant; 1988-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Boral Resources Inc → Fontana Plant; 1988-06-10 to 1995-06-14; source msha-controller-operator-history
- **controller_controls_operator:** Boral Limited → Boral Resources Inc; 1988-06-10 to 1995-06-14; source msha-controller-operator-history
- **controller_controls_mine:** Hanson PLC → Fontana Plant; 1988-11-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Livingston Graham/Blue Diamond Materials → Fontana Plant; 1995-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hanson PLC → Livingston Graham/Blue Diamond Materials; 1995-06-15 to current/open; source msha-controller-operator-history