# Relationship history for MSHA mine 4300704

Current hierarchy: **Bruce W  Pion → Navigator Environmental Services → B&L Pion Sand & Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Navigator Environmental Services → B&L Pion Sand & Gravel; 2009-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bruce W  Pion → B&L Pion Sand & Gravel; 2009-05-12 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce W  Pion → Navigator Environmental Services; 2009-05-12 to current/open; source msha-controller-operator-history