# Relationship history for MSHA mine 3503426

Current hierarchy: **CRH PLC → American Rock Products Inc → ARP Westgate Quarry**

- 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

- **controller_controls_mine:** CRH PLC → ARP Westgate Quarry; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → ARP Westgate Quarry; 1987-09-18 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Aaa-Concrete & Asphalt → ARP Westgate Quarry; 1996-03-01 to 1997-03-31; source msha-controller-operator-history
- **controller_controls_mine:** North Central Construction → ARP Westgate Quarry; 1996-03-01 to 1997-03-31; source msha-controller-operator-history
- **controller_controls_operator:** North Central Construction → Aaa-Concrete & Asphalt; 1996-03-01 to 1997-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Central Pre-Mix Of Oregon → ARP Westgate Quarry; 1997-04-01 to 2020-08-11; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Central Pre-Mix Of Oregon; 1997-04-01 to 2020-08-11; source msha-controller-operator-history
- **operator_operates_mine:** American Rock Products Inc → ARP Westgate Quarry; 2020-08-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → American Rock Products Inc; 2020-08-12 to current/open; source msha-controller-operator-history