# Relationship history for MSHA mine 2103389

Current hierarchy: **Brian D  Gruhot → D & G Excavating Inc → Powerscreen Rock Separator**

- 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:** Brian D  Gruhot → Powerscreen Rock Separator; 2003-07-16 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** D & G Excavating Inc → Powerscreen Rock Separator; 2003-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brian D  Gruhot → D & G Excavating Inc; 2003-08-04 to current/open; source msha-controller-operator-history