# Relationship history for MSHA mine 2700208

Current hierarchy: **Brox Industries Inc → Brox Paving Materials Inc → Belmont N H Plant**

- 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:** Belmont Sand & Gravel Inc → Belmont N H Plant; 1950-01-01 to 1988-04-07; source msha-controller-operator-history
- **controller_controls_mine:** Salta Nicky → Belmont N H Plant; 1950-01-01 to 1988-04-07; source msha-controller-operator-history
- **controller_controls_operator:** Salta Nicky → Belmont Sand & Gravel Inc; 1950-01-01 to 1988-04-07; source msha-controller-operator-history
- **operator_operates_mine:** Brox Paving Materials Inc → Belmont N H Plant; 1988-04-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brox Industries Inc → Belmont N H Plant; 1988-04-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brox Industries Inc → Brox Paving Materials Inc; 1988-04-08 to current/open; source msha-controller-operator-history