# Relationship history for MSHA mine 2003506

Current hierarchy: **Andy  Ross; Matthew  Joniec → Todd's Welding Service → Wood Road NW 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Todd's Welding Service, Inc. → Wood Road NW Pit; 2015-03-26 to 2026-03-08; source msha-controller-operator-history
- **controller_controls_mine:** Todd E  Chwastek → Wood Road NW Pit; 2015-03-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Todd E  Chwastek → Todd's Welding Service, Inc.; 2015-03-26 to 2026-03-08; source msha-controller-operator-history
- **operator_operates_mine:** Todd's Welding Service → Wood Road NW Pit; 2026-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Andy  Ross et al → Wood Road NW Pit; 2026-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Andy  Ross et al → Todd's Welding Service; 2026-03-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matthew  Joniec → Todd's Welding Service; 2026-03-09 to current/open; source msha-controller-operator-history