# Relationship history for MSHA mine 3901458

Current hierarchy: **Gary  Baker; Jim  Baker → BADLANDS SAND & GRAVEL → PORTABLE #1**

- 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:** Badlands Sand & Gravel → PORTABLE #1; 2001-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gary  Baker  et al → PORTABLE #1; 2001-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary  Baker  et al → Badlands Sand & Gravel; 2001-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jim  Baker  et al → Badlands Sand & Gravel; 2001-03-15 to current/open; source msha-controller-operator-history