# Relationship history for MSHA mine 4609560

Current hierarchy: **John Mitch Potter → Coal Mac East → North Fork Surface 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

- **controller_controls_mine:** Coronado Coal LLC → North Fork Surface Mine; 2013-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Greenbrier Minerals, LLC → North Fork Surface Mine; 2018-10-03 to 2026-07-31; source msha-controller-operator-history
- **controller_controls_operator:** Coronado Coal LLC → Greenbrier Minerals, LLC; 2018-10-03 to 2026-07-31; source msha-controller-operator-history
- **operator_operates_mine:** Coal Mac East → North Fork Surface Mine; 2026-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** John Mitch Potter → North Fork Surface Mine; 2026-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** John Mitch Potter → Coal Mac East; 2026-08-01 to current/open; source msha-controller-operator-history