# Relationship history for MSHA mine 0503627

Current hierarchy: **Redland Plc → Western Paving Construction Company → Del Camino Pit**

- 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:** Koppers Company Inc → Del Camino Pit; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Western Paving Construction Company → Del Camino Pit; 1980-11-01 to 1987-05-28; source msha-controller-operator-history
- **controller_controls_operator:** Koppers Company Inc → Western Paving Construction Company; 1980-11-01 to 1987-05-28; source msha-controller-operator-history
- **operator_operates_mine:** Western Paving Construction Company → Del Camino Pit; 1987-05-29 to 1988-06-13; source msha-controller-operator-history
- **controller_controls_mine:** Koppers Co Inc & Redland Plc → Del Camino Pit; 1987-05-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Koppers Co Inc & Redland Plc → Western Paving Construction Company; 1987-05-29 to 1988-06-13; source msha-controller-operator-history
- **operator_operates_mine:** Western Paving Construction Company → Del Camino Pit; 1988-06-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Redland Plc → Del Camino Pit; 1988-06-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Redland Plc → Western Paving Construction Company; 1988-06-14 to current/open; source msha-controller-operator-history