# Relationship history for MSHA mine 4503461

Current hierarchy: **Mike E  Green → Discovery Bay Materials → Pit #1**

- 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:** M & E Trucking & Construction → Pit #1; 2000-09-01 to 2005-03-27; source msha-controller-operator-history
- **controller_controls_mine:** Earl A Green → Pit #1; 2000-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Earl A Green → M & E Trucking & Construction; 2000-09-01 to 2005-03-27; source msha-controller-operator-history
- **operator_operates_mine:** Discovery Bay Materials → Pit #1; 2005-03-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mike E  Green → Pit #1; 2005-03-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mike E  Green → Discovery Bay Materials; 2005-03-29 to current/open; source msha-controller-operator-history