# Relationship history for MSHA mine 1513271

Current hierarchy: **Coal Ridge Fuels Of Hazard Inc → River Processing Inc → #2 Surface**

- 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

- **controller_controls_mine:** Pargas Inc → #2 Surface; 1973-03-22 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Grae Mining Inc → #2 Surface; 1981-12-01 to 1982-09-07; source msha-controller-operator-history
- **controller_controls_mine:** Large Roger → #2 Surface; 1981-12-01 to 1982-09-07; source msha-controller-operator-history
- **controller_controls_operator:** Large Roger → Grae Mining Inc; 1981-12-01 to 1982-09-07; source msha-controller-operator-history
- **operator_operates_mine:** River Processing Inc → #2 Surface; 1982-09-08 to 1983-12-20; source msha-controller-operator-history
- **controller_controls_operator:** Pargas Inc → River Processing Inc; 1982-09-08 to 1983-12-20; source msha-controller-operator-history
- **operator_operates_mine:** River Processing Inc → #2 Surface; 1983-12-21 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Coal Ridge Fuels Of Hazard Inc → #2 Surface; 1983-12-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Coal Ridge Fuels Of Hazard Inc → River Processing Inc; 1983-12-21 to current/open; source msha-controller-operator-history