# Relationship history for MSHA mine 0503969

Current hierarchy: **Koppers Co Inc & Redland Plc → Western Paving Construction Company → Turkey Flats Pit 17**

- 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 → Turkey Flats Pit 17; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Western Paving Construction Company → Turkey Flats Pit 17; 1984-07-01 to 1987-05-28; source msha-controller-operator-history
- **controller_controls_operator:** Koppers Company Inc → Western Paving Construction Company; 1984-07-01 to 1987-05-28; source msha-controller-operator-history
- **operator_operates_mine:** Western Paving Construction Company → Turkey Flats Pit 17; 1987-05-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Koppers Co Inc & Redland Plc → Turkey Flats Pit 17; 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 current/open; source msha-controller-operator-history