# Relationship history for MSHA mine 4702625

Current hierarchy: **Wissota Sand & Gravel Company → Winona Aggregate Company → Tank Creek Sand And Gravel Co**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Wissota Sand & Gravel Company → Tank Creek Sand And Gravel Co; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Winona Aggregate Company → Tank Creek Sand And Gravel Co; 1979-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wissota Sand & Gravel Company → Winona Aggregate Company; 1979-01-01 to current/open; source msha-controller-operator-history