# Relationship history for MSHA mine 3401084

Current hierarchy: **Edmondson Bill → B & B Sand & Topsoil Company → B & B Sand Pit**

- 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:** Acme Sand Div/Tri-Angle Development Company Inc → B & B Sand Pit; 1978-03-09 to 1985-08-28; source msha-controller-operator-history
- **controller_controls_mine:** Tri-Angle Development Company Inc → B & B Sand Pit; 1978-03-09 to 1985-08-28; source msha-controller-operator-history
- **controller_controls_operator:** Tri-Angle Development Company Inc → Acme Sand Div/Tri-Angle Development Company Inc; 1978-03-09 to 1985-08-28; source msha-controller-operator-history
- **operator_operates_mine:** B & B Sand & Topsoil Company → B & B Sand Pit; 1985-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Edmondson Bill → B & B Sand Pit; 1985-08-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Edmondson Bill → B & B Sand & Topsoil Company; 1985-08-29 to current/open; source msha-controller-operator-history