# Relationship history for MSHA mine 4105385

Current hierarchy: **Elias  Rodriguez; Nilda  Rodriguez → Imperial Sand & Gravel → Imperial Sand & Gravel-Grandfalls**

- 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:** Nilda  Rodriguez et al → Imperial Sand & Gravel-Grandfalls; 2017-09-07 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Imperial Sand & Gravel → Imperial Sand & Gravel-Grandfalls; 2018-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Nilda  Rodriguez et al → Imperial Sand & Gravel; 2018-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elias  Rodriguez et al → Imperial Sand & Gravel; 2018-08-29 to current/open; source msha-controller-operator-history