# Relationship history for MSHA mine 4103675

Current hierarchy: **Walter  Koepp → Waw Trucking Company Inc → Waw Sand Company**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Womack Diesel Service Inc → Waw Sand Company; 1991-05-01 to 1994-11-08; source msha-controller-operator-history
- **controller_controls_mine:** Charlie  Womack → Waw Sand Company; 1991-05-01 to 1994-11-08; source msha-controller-operator-history
- **controller_controls_operator:** Charlie  Womack → Womack Diesel Service Inc; 1991-05-01 to 1994-11-08; source msha-controller-operator-history
- **operator_operates_mine:** Waw Trucking Company Inc → Waw Sand Company; 1994-11-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Walter  Koepp → Waw Sand Company; 1994-11-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walter  Koepp → Waw Trucking Company Inc; 1994-11-09 to current/open; source msha-controller-operator-history