# Relationship history for MSHA mine 0404851

Current hierarchy: **Hendrix Brent → Dirtman Trucking → Dirtman Sand & Gravel #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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Pioneer Sand Gravel & Rockery → Dirtman Sand & Gravel #2; 1986-11-01 to 1988-03-21; source msha-controller-operator-history
- **controller_controls_mine:** Lew K  Borzini → Dirtman Sand & Gravel #2; 1986-11-01 to 1988-03-21; source msha-controller-operator-history
- **controller_controls_operator:** Lew K  Borzini → Pioneer Sand Gravel & Rockery; 1986-11-01 to 1988-03-21; source msha-controller-operator-history
- **operator_operates_mine:** Dirtman Trucking → Dirtman Sand & Gravel #2; 1988-03-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Hendrix Brent → Dirtman Sand & Gravel #2; 1988-03-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hendrix Brent → Dirtman Trucking; 1988-03-22 to current/open; source msha-controller-operator-history