# Relationship history for MSHA mine 5001312

Current hierarchy: ** → Delta Concrete Products Inc → Delta Pit & 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:** Delta Concrete Products Inc → Delta Pit & Plant; 1980-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Collum Douglas → Delta Pit & Plant; 1980-02-01 to 2003-09-09; source msha-controller-operator-history
- **controller_controls_operator:** Mc Collum Douglas → Delta Concrete Products Inc; 1980-02-01 to 2003-09-09; source msha-controller-operator-history
- **controller_controls_mine:** Matthew J  Walker → Delta Pit & Plant; 2003-09-10 to 2022-06-23; source msha-controller-operator-history
- **controller_controls_operator:** Matthew J  Walker → Delta Concrete Products Inc; 2003-09-10 to 2022-06-23; source msha-controller-operator-history