# Relationship history for MSHA mine 0404679

Current hierarchy: **Eric  Schoonmaker; Madelyn  Schoonmaker → Contractors Sand & Gravel Supply Inc → MONATGUE 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

- **controller_controls_mine:** Eric  Schoonmaker  et al → MONATGUE PLANT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Contractors Sand & Gravel Supply Inc → MONATGUE PLANT; 1984-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eric  Schoonmaker  et al → Contractors Sand & Gravel Supply Inc; 1984-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Madelyn  Schoonmaker  et al → Contractors Sand & Gravel Supply Inc; 1984-01-01 to current/open; source msha-controller-operator-history