# Relationship history for MSHA mine 4500644

Current hierarchy: **Rhonda  Schroeder → Jones-Scott Company → Walla Walla 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:** Jones Scott Company → Walla Walla Plant; 1950-01-01 to 1980-07-16; source msha-controller-operator-history
- **controller_controls_mine:** Jack M  Morrison → Walla Walla Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jack M  Morrison → Jones Scott Company; 1950-01-01 to 1980-07-16; source msha-controller-operator-history
- **operator_operates_mine:** Jones-Scott Company → Walla Walla Plant; 1980-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Rhonda  Schroeder → Walla Walla Plant; 1980-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rhonda  Schroeder → Jones-Scott Company; 1980-07-17 to current/open; source msha-controller-operator-history