# Relationship history for MSHA mine 2102894

Current hierarchy: **James A  Anderson → J & S Gravel Inc → Fabtec Wash 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:** J & S Gravel Inc → Fabtec Wash Plant; 1982-09-01 to 1989-07-10; source msha-controller-operator-history
- **controller_controls_mine:** Richard N  Johnson et al → Fabtec Wash Plant; 1982-09-01 to 1989-07-10; source msha-controller-operator-history
- **controller_controls_operator:** Richard N  Johnson et al → J & S Gravel Inc; 1982-09-01 to 1989-07-10; source msha-controller-operator-history
- **operator_operates_mine:** J & S Gravel Inc → Fabtec Wash Plant; 1989-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** James A  Anderson → Fabtec Wash Plant; 1989-07-11 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James A  Anderson → J & S Gravel Inc; 1989-07-11 to current/open; source msha-controller-operator-history