# Relationship history for MSHA mine 4300481

Current hierarchy: **Town Of Rockingham-VT → Town Of Rockingham → TOWN OF ROCKINGHAM GRAVEL 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Town Of Rockingham → TOWN OF ROCKINGHAM GRAVEL PIT; 1992-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Town Of Rockingham-VT → TOWN OF ROCKINGHAM GRAVEL PIT; 1992-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Town Of Rockingham-VT → Town Of Rockingham; 1992-10-01 to current/open; source msha-controller-operator-history