# Relationship history for MSHA mine 1518415

Current hierarchy: **CRH PLC → Hinkle Contracting Company LLC → Bourbon Limestone Company**

- 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:** Summit Materials LLC → Bourbon Limestone Company; 1950-01-01 to 2022-05-13; source msha-controller-operator-history
- **controller_controls_mine:** Arthur E  Walker III et al → Bourbon Limestone Company; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Bourbon Limestone Company → Bourbon Limestone Company; 2001-07-01 to 2011-05-30; source msha-controller-operator-history
- **controller_controls_operator:** Arthur E  Walker III et al → Bourbon Limestone Company; 2001-07-01 to 2011-05-30; source msha-controller-operator-history
- **controller_controls_operator:** Thomas S  Hinkle  et al → Bourbon Limestone Company; 2001-07-01 to 2011-05-30; source msha-controller-operator-history
- **operator_operates_mine:** Hinkle Contracting Company LLC → Bourbon Limestone Company; 2011-05-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Summit Materials LLC → Hinkle Contracting Company LLC; 2011-05-31 to 2022-05-13; source msha-controller-operator-history
- **controller_controls_mine:** CRH PLC → Bourbon Limestone Company; 2022-05-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** CRH PLC → Hinkle Contracting Company LLC; 2022-05-14 to current/open; source msha-controller-operator-history