# Relationship history for MSHA mine 4103279

Current hierarchy: **Wood Paul A → Wood Sand & Gravel Inc → Plant No 1 & Plant No 2**

- 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

- **operator_operates_mine:** Wood Sand & Gravel Inc → Plant No 1 & Plant No 2; 1984-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Wood Paul A → Plant No 1 & Plant No 2; 1984-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Wood Paul A → Wood Sand & Gravel Inc; 1984-12-01 to current/open; source msha-controller-operator-history