# Relationship history for MSHA mine 4105567

Current hierarchy: **Ruben  Salinas Sr → Columbus Sand & Gravel LLC → Columbus Sand & Gravel LCC Plant 2**

- 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

- **controller_controls_mine:** Ruben  Salinas Sr → Columbus Sand & Gravel LCC Plant 2; 2017-01-17 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Columbus Sand & Gravel LLC → Columbus Sand & Gravel LCC Plant 2; 2021-06-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ruben  Salinas Sr → Columbus Sand & Gravel LLC; 2021-06-30 to current/open; source msha-controller-operator-history