# Relationship history for MSHA mine 2103723

Current hierarchy: **William A  Snidarich → Dirt Doctor Inc → Rock Lake Plant**

- 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:** Dirt Doctor Inc → Rock Lake Plant; 2010-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** William A  Snidarich → Rock Lake Plant; 2010-09-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** William A  Snidarich → Dirt Doctor Inc; 2010-09-27 to current/open; source msha-controller-operator-history