# Relationship history for MSHA mine 3601506

Current hierarchy: **Walker Alvy A Jr & Thomas E Turner → Conrad Mining Company → Conrad #1 Mine**

- 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:** Potochar & Potochar Coal Company → Conrad #1 Mine; 1970-05-01 to 1983-03-06; source msha-controller-operator-history
- **controller_controls_mine:** Potochar Joseph H → Conrad #1 Mine; 1970-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Potochar Joseph H → Potochar & Potochar Coal Company; 1970-05-01 to 1983-03-06; source msha-controller-operator-history
- **operator_operates_mine:** Conrad Mining Company → Conrad #1 Mine; 1983-03-07 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Walker Alvy A Jr & Thomas E Turner → Conrad #1 Mine; 1983-03-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Walker Alvy A Jr & Thomas E Turner → Conrad Mining Company; 1983-03-07 to current/open; source msha-controller-operator-history