# Relationship history for MSHA mine 1000326

Current hierarchy: **CRH PLC → Idaho Materials & Construction → Mt Home Portable**

- 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:** Idaho Concrete Company Inc → Mt Home Portable; 1950-01-01 to 2000-03-26; source msha-controller-operator-history
- **controller_controls_mine:** Robert L  Rice et al → Mt Home Portable; 1950-01-01 to 2000-03-26; source msha-controller-operator-history
- **controller_controls_operator:** Robert L  Rice et al → Idaho Concrete Company Inc; 1950-01-01 to 2000-03-26; source msha-controller-operator-history
- **operator_operates_mine:** Idaho Materials & Construction → Mt Home Portable; 2000-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Mt Home Portable; 2000-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Idaho Materials & Construction; 2000-03-27 to current/open; source msha-controller-operator-history