# Relationship history for MSHA mine 4503020

Current hierarchy: **Albert E  DeAtley → Basin Asphalt Company → Portable Crusher**

- 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:** Albert E  DeAtley → Portable Crusher; 1981-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Basin Asphalt Company → Portable Crusher; 1984-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Albert E  DeAtley → Basin Asphalt Company; 1984-07-01 to current/open; source msha-controller-operator-history