# Relationship history for MSHA mine 5001827

Current hierarchy: **Erik D  Bolshakoff → Erik Bolshakoff → Big Rock Trucking**

- 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:** Ward Cove Construction → Big Rock Trucking; 2005-09-19 to 2014-06-09; source msha-controller-operator-history
- **controller_controls_mine:** Merrill M Stulken → Big Rock Trucking; 2005-09-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Merrill M Stulken → Ward Cove Construction; 2005-09-19 to 2014-06-09; source msha-controller-operator-history
- **operator_operates_mine:** Erik Bolshakoff → Big Rock Trucking; 2014-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Erik D  Bolshakoff → Big Rock Trucking; 2014-06-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Erik D  Bolshakoff → Erik Bolshakoff; 2014-06-10 to current/open; source msha-controller-operator-history