# Relationship history for MSHA mine 0102840

Current hierarchy: **Roberts Bill → Flint River Sand & Gravel Company Inc → Flint River Mine**

- 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:** Flint River Sand & Gravel Company Inc → Flint River Mine; 1989-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roberts Bill → Flint River Mine; 1989-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roberts Bill → Flint River Sand & Gravel Company Inc; 1989-12-01 to current/open; source msha-controller-operator-history