# Relationship history for MSHA mine 4608303

Current hierarchy: **El Paso Energy Corp → Greenbrier Coal Company → Clearco Preparation 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:** Greenbrier Coal Company → Clearco Preparation Plant; 1993-05-01 to 1993-08-15; source msha-controller-operator-history
- **controller_controls_mine:** El Paso Energy Corp → Clearco Preparation Plant; 1993-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** El Paso Energy Corp → Greenbrier Coal Company; 1993-05-01 to 1993-08-15; source msha-controller-operator-history
- **operator_operates_mine:** Beitzel Corp → Clearco Preparation Plant; 1993-08-16 to 1994-06-23; source msha-controller-operator-history
- **controller_controls_mine:** Beitzel Olen → Clearco Preparation Plant; 1993-08-16 to 1994-06-23; source msha-controller-operator-history
- **controller_controls_operator:** Beitzel Olen → Beitzel Corp; 1993-08-16 to 1994-06-23; source msha-controller-operator-history
- **operator_operates_mine:** Greenbrier Coal Company → Clearco Preparation Plant; 1994-06-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** El Paso Energy Corp → Greenbrier Coal Company; 1994-06-24 to current/open; source msha-controller-operator-history