# Relationship history for MSHA mine 2100022

Current hierarchy: **Patrick  Alexander; Michael  O'Connor → Cold Spring Granite Company → ROCKVILLE #1 QUARRY**

- 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:** Cold Spring Granite Company → ROCKVILLE #1 QUARRY; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Patrick  Alexander → ROCKVILLE #1 QUARRY; 1950-01-01 to 2024-05-20; source msha-controller-operator-history
- **controller_controls_operator:** Patrick  Alexander → Cold Spring Granite Company; 1950-01-01 to 2024-05-20; source msha-controller-operator-history
- **controller_controls_mine:** Patrick  Alexander → ROCKVILLE #1 QUARRY; 2024-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick  Alexander → Cold Spring Granite Company; 2024-05-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael  O'Connor → Cold Spring Granite Company; 2024-05-21 to current/open; source msha-controller-operator-history