# Relationship history for MSHA mine 4503579

Current hierarchy: **David  Creagan → American Crushing & Recycling → Portable Screen 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

- **controller_controls_mine:** David  Creagan → Portable Screen Plant; 2005-04-25 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** American Crushing & Recycling → Portable Screen Plant; 2005-05-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** David  Creagan → American Crushing & Recycling; 2005-05-04 to current/open; source msha-controller-operator-history