# Relationship history for MSHA mine 4702987

Current hierarchy: **Steven  Haas; Gary  Haas → Haas Sons Inc → Wash Plant #2**

- 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

- **controller_controls_mine:** Steven  Haas et al → Wash Plant #2; 1985-08-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Haas Sons Inc → Wash Plant #2; 1993-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steven  Haas et al → Haas Sons Inc; 1993-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary  Haas et al → Haas Sons Inc; 1993-04-01 to current/open; source msha-controller-operator-history