# Relationship history for MSHA mine 2103036

Current hierarchy: **Doug  Schuur; Darren  Schuur → Schuur Concrete LLC → Chandler Wash 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:** Schuur Concrete → Chandler Wash Plant; 1991-06-01 to 2019-03-31; source msha-controller-operator-history
- **controller_controls_mine:** Milt  Schuur et al → Chandler Wash Plant; 1991-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Milt  Schuur et al → Schuur Concrete; 1991-06-01 to 2019-03-31; source msha-controller-operator-history
- **operator_operates_mine:** Schuur Concrete LLC → Chandler Wash Plant; 2019-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Doug  Schuur et al → Chandler Wash Plant; 2019-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Doug  Schuur et al → Schuur Concrete LLC; 2019-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Darren  Schuur et al → Schuur Concrete LLC; 2019-04-01 to current/open; source msha-controller-operator-history