# Relationship history for MSHA mine 0504941

Current hierarchy: **Justin  Helmer → Zen Excavation, Inc → McNulty Cinder Pit**

- 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:** Zen Excavation, Inc → McNulty Cinder Pit; 2009-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Justin  Helmer → McNulty Cinder Pit; 2009-07-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Justin  Helmer → Zen Excavation, Inc; 2009-07-10 to current/open; source msha-controller-operator-history