# Relationship history for MSHA mine 4801860

Current hierarchy: **Matt  Garland; Matthew W  Garland → Powder River Sand and Gravel → Fabtech Wash 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:** Powder River Sand and Gravel → Fabtech Wash Plant; 2022-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Matt  Garland et al → Fabtech Wash Plant; 2022-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matt  Garland et al → Powder River Sand and Gravel; 2022-10-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Matthew W  Garland et al → Powder River Sand and Gravel; 2022-10-25 to current/open; source msha-controller-operator-history