# Relationship history for MSHA mine 0401846

Current hierarchy: **Teichert Inc → Santa Fe Aggregates Inc → WATERFORD PIT & MILL**

- 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:** Santa Fe Rock & Sand → WATERFORD PIT & MILL; 1950-01-01 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_mine:** M J  Ruddy Jr → WATERFORD PIT & MILL; 1950-01-01 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_operator:** M J  Ruddy Jr → Santa Fe Rock & Sand; 1950-01-01 to 1988-12-05; source msha-controller-operator-history
- **controller_controls_mine:** Teichert Inc → WATERFORD PIT & MILL; 1988-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Santa Fe Aggregates Inc → WATERFORD PIT & MILL; 1988-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Teichert Inc → Santa Fe Aggregates Inc; 1988-12-06 to current/open; source msha-controller-operator-history