# Relationship history for MSHA mine 4606319

Current hierarchy: **Bolinger Ronald D → Bolingreen Mining Company → Bolingreen 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:** Hilltop Coal Company → Bolingreen Mine; 1981-04-01 to 1982-11-30; source msha-controller-operator-history
- **controller_controls_mine:** Shafer Olaf → Bolingreen Mine; 1981-04-01 to 1982-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Shafer Olaf → Hilltop Coal Company; 1981-04-01 to 1982-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Bolingreen Mining Company → Bolingreen Mine; 1982-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bolinger Ronald D → Bolingreen Mine; 1982-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bolinger Ronald D → Bolingreen Mining Company; 1982-12-01 to current/open; source msha-controller-operator-history