# Relationship history for MSHA mine 1518199

Current hierarchy: **Carbontronics Synfuels Investors Lp → PC Kentucky Synthetic Fuel #3, LLC → #1 Dredge**

- 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:** PC Kentucky Synthetic Fuel #3, LLC → #1 Dredge; 1999-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Carbontronics Synfuels Investors Lp → #1 Dredge; 1999-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Carbontronics Synfuels Investors Lp → PC Kentucky Synthetic Fuel #3, LLC; 1999-08-01 to current/open; source msha-controller-operator-history