# Relationship history for MSHA mine 0300005

Current hierarchy: **CRH PLC → Arkhola Sand & Gravel Company → Alma Quarry & Plant Or Alma Quarry & Mil**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Arkhola Sand & Gravel Company → Alma Quarry & Plant Or Alma Quarry & Mil; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc → Alma Quarry & Plant Or Alma Quarry & Mil; 1950-01-01 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Arkhola Sand & Gravel Company; 1950-01-01 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Alma Quarry & Plant Or Alma Quarry & Mil; 2006-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Arkhola Sand & Gravel Company; 2006-08-28 to current/open; source msha-controller-operator-history