# Relationship history for MSHA mine 3609857

Current hierarchy: **Stephen  Hess; Scott  Hess → Daggett Sand & Gravel Inc → Portable Eagle 1200 Crusher Serial #30087**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Stephen  Hess et al → Portable Eagle 1200 Crusher Serial #3008; 1997-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Daggett Sand & Gravel Inc → Portable Eagle 1200 Crusher Serial #3008; 2010-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Stephen  Hess et al → Daggett Sand & Gravel Inc; 2010-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Scott  Hess et al → Daggett Sand & Gravel Inc; 2010-10-01 to current/open; source msha-controller-operator-history