# Relationship history for MSHA mine 0503992

Current hierarchy: **Estate of Henry T. Southway Jr. → Southwest Ready Mix Inc → Swift 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Southwest Ready-Mix Inc Of Alamosa → Swift Pit; 1984-10-01 to 2003-03-13; source msha-controller-operator-history
- **controller_controls_mine:** Estate of Henry T. Southway Jr. → Swift Pit; 1984-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Estate of Henry T. Southway Jr. → Southwest Ready-Mix Inc Of Alamosa; 1984-10-01 to 2003-03-13; source msha-controller-operator-history
- **controller_controls_mine:** Estate of Henry T. Southway Jr. → Swift Pit; 1986-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Southwest Ready Mix Inc → Swift Pit; 2003-03-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Estate of Henry T. Southway Jr. → Southwest Ready Mix Inc; 2003-03-14 to current/open; source msha-controller-operator-history