# Relationship history for MSHA mine 4405231

Current hierarchy: **Senter Robert → Amy'S Salvage → Processing 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: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Amy'S Salvage → Processing Plant; 1979-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Senter Robert Et Al → Processing Plant; 1979-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Senter Robert Et Al → Amy'S Salvage; 1979-03-01 to current/open; source msha-controller-operator-history