# Relationship history for MSHA mine 2302042

Current hierarchy: **CRH PLC → Apac-Missouri Inc → Sand 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:** Hall & Riley Paving Company Inc → Sand Plant; 1991-06-01 to 2000-12-13; source msha-controller-operator-history
- **controller_controls_mine:** Hall & Riley Quarries & Construction Company Inc → Sand Plant; 1991-06-01 to 2000-12-13; source msha-controller-operator-history
- **controller_controls_operator:** Hall & Riley Quarries & Construction Company Inc → Hall & Riley Paving Company Inc; 1991-06-01 to 2000-12-13; source msha-controller-operator-history
- **controller_controls_mine:** Ashland Inc → Sand Plant; 1998-02-03 to 2006-08-27; source msha-controller-operator-history
- **operator_operates_mine:** Apac-Missouri Inc → Sand Plant; 2000-12-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Apac-Missouri Inc; 2000-12-14 to 2006-08-27; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Sand Plant; 2006-08-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Apac-Missouri Inc; 2006-08-28 to current/open; source msha-controller-operator-history