# Relationship history for MSHA mine 1700939

Current hierarchy: **Roy J  Trombley; Craig R  Trombley → Trombley Redi-Mix → Madawaska Plant**

- 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

- **operator_operates_mine:** Trombley Redi-Mix → Madawaska Plant; 2014-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy J  Trombley et al → Madawaska Plant; 2014-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy J  Trombley et al → Trombley Redi-Mix; 2014-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Craig R  Trombley et al → Trombley Redi-Mix; 2014-06-24 to current/open; source msha-controller-operator-history