# Relationship history for MSHA mine 4703979

Current hierarchy: **Greg  Kolodziej → North Central Aggregates LLC → Portable Screen #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **controller_controls_mine:** Greg  Kolodziej → Portable Screen #2; 2024-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** North Central Aggregates LLC → Portable Screen #2; 2025-06-05 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greg  Kolodziej → North Central Aggregates LLC; 2025-06-05 to current/open; source msha-controller-operator-history