# Relationship history for MSHA mine 0301509

Current hierarchy: **West Thomas W → Process Plant Operators Inc → Bonanza 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** G N C Energy Corp → Bonanza Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Great National Corp-Nevada → Bonanza Plant; 1981-03-01 to 1988-08-10; source msha-controller-operator-history
- **controller_controls_operator:** G N C Energy Corp → Great National Corp-Nevada; 1981-03-01 to 1988-08-10; source msha-controller-operator-history
- **controller_controls_mine:** Davis Barry M → Bonanza Plant; 1986-12-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Davis Coal Corp → Bonanza Plant; 1988-08-11 to 1989-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Davis Barry M → Davis Coal Corp; 1988-08-11 to 1989-08-31; source msha-controller-operator-history
- **operator_operates_mine:** Process Plant Operators → Bonanza Plant; 1989-09-01 to 1989-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Walker J L → Bonanza Plant; 1989-09-01 to 1989-12-31; source msha-controller-operator-history
- **controller_controls_operator:** Walker J L → Process Plant Operators; 1989-09-01 to 1989-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Process Plant Operators Inc → Bonanza Plant; 1990-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** West Thomas W → Bonanza Plant; 1990-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** West Thomas W → Process Plant Operators Inc; 1990-01-01 to current/open; source msha-controller-operator-history