# Relationship history for MSHA mine 4102534

Current hierarchy: **Tarmac Plc → Cen-Tex Ready Mix Concrete Company → Mound 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:** Belton Sand & Gravel Company Inc → Mound Plant; 1950-01-01 to 1985-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Great Western Drilling Company → Mound Plant; 1950-01-01 to 1985-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Great Western Drilling Company → Belton Sand & Gravel Company Inc; 1950-01-01 to 1985-02-28; source msha-controller-operator-history
- **operator_operates_mine:** Cen-Tex Ready Mix Concrete Company → Mound Plant; 1985-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tarmac Plc → Mound Plant; 1985-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tarmac Plc → Cen-Tex Ready Mix Concrete Company; 1985-03-01 to current/open; source msha-controller-operator-history