# Relationship history for MSHA mine 4501288

Current hierarchy: **Leita Marvelle → Triangle Sand & Gravel Company Inc → Portable 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:** Superior Asphalt & Concrete → Portable Plant; 1950-01-01 to 1978-12-05; source msha-controller-operator-history
- **controller_controls_mine:** Albert E  DeAtley → Portable Plant; 1950-01-01 to 1978-12-05; source msha-controller-operator-history
- **controller_controls_operator:** Albert E  DeAtley → Superior Asphalt & Concrete; 1950-01-01 to 1978-12-05; source msha-controller-operator-history
- **operator_operates_mine:** Triangle Sand & Gravel Company Inc → Portable Plant; 1978-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Leita Marvelle → Portable Plant; 1978-12-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Leita Marvelle → Triangle Sand & Gravel Company Inc; 1978-12-06 to current/open; source msha-controller-operator-history