# Relationship history for MSHA mine 5001523

Current hierarchy: **Christenson Raber Kief & Assoc Inc & Walsh & Co In → Aleutian Constructors → Tuxedo 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Aleutian Constructors → Tuxedo Quarry; 1987-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Christenson Raber Kief & Assoc Inc & Walsh & Co In → Tuxedo Quarry; 1987-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christenson Raber Kief & Assoc Inc & Walsh & Co In → Aleutian Constructors; 1987-07-01 to current/open; source msha-controller-operator-history