# Relationship history for MSHA mine 4703643

Current hierarchy: **Tim R  Barth; Tom J  Griffith → Sand Technologies LLC → Plattes Valley Sand**

- 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:** Sand Technologies LLC → Plattes Valley Sand; 2012-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tom J  Griffith et al → Plattes Valley Sand; 2012-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tom J  Griffith et al → Sand Technologies LLC; 2012-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tim R  Barth et al → Sand Technologies LLC; 2012-05-01 to current/open; source msha-controller-operator-history