# Relationship history for MSHA mine 3503110

Current hierarchy: **Afab Inc & Trgr Oregon Ltd → Excavated Materials Processing Company → Empco 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:** Excavated Materials Processing Company → Empco Plant; 1983-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Afab Inc & Trgr Oregon Ltd → Empco Plant; 1983-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Afab Inc & Trgr Oregon Ltd → Excavated Materials Processing Company; 1983-04-01 to current/open; source msha-controller-operator-history