# Relationship history for MSHA mine 4002444

Current hierarchy: **Fortner Ralph → Elk Valley Coal Corp → No 1 Prep Plant**

- 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:** Elk-Jay Coal Company → No 1 Prep Plant; 1978-08-01 to 1979-11-18; source msha-controller-operator-history
- **controller_controls_mine:** Elk Valley Coal Corp Et Al → No 1 Prep Plant; 1978-08-01 to 1979-11-18; source msha-controller-operator-history
- **controller_controls_operator:** Elk Valley Coal Corp Et Al → Elk-Jay Coal Company; 1978-08-01 to 1979-11-18; source msha-controller-operator-history
- **operator_operates_mine:** Elk Valley Coal Corp → No 1 Prep Plant; 1979-11-19 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Fortner Ralph → No 1 Prep Plant; 1979-11-19 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Fortner Ralph → Elk Valley Coal Corp; 1979-11-19 to current/open; source msha-controller-operator-history