# Relationship history for MSHA mine 5001912

Current hierarchy: **United States Government → USDI National Park Service → DENA Mobile Screen Plant #2**

- 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

- **controller_controls_mine:** United States Government → DENA Mobile Screen Plant #2; 2003-05-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** USDI National Park Service → DENA Mobile Screen Plant #2; 2009-07-09 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** United States Government → USDI National Park Service; 2009-07-09 to current/open; source msha-controller-operator-history