# Relationship history for MSHA mine 0504745

Current hierarchy: **Colas S A → Simon Contractors → Harriman 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

- **controller_controls_mine:** Colas S A → Harriman Quarry; 1995-01-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert C  Willits → Harriman Quarry; 1997-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Willits Company Inc. → Harriman Quarry; 2002-01-23 to 2016-06-16; source msha-controller-operator-history
- **controller_controls_operator:** Robert C  Willits → Willits Company Inc.; 2002-01-23 to 2016-06-16; source msha-controller-operator-history
- **operator_operates_mine:** Simon Contractors → Harriman Quarry; 2016-06-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Colas S A → Simon Contractors; 2016-06-17 to current/open; source msha-controller-operator-history