# Relationship history for MSHA mine 2103283

Current hierarchy: **Kevin M  Monson → Riverside Sand & Gravel → RIVERSIDE SAND & GRAVEL**

- 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:** Riverside Sand & Gravel → RIVERSIDE SAND & GRAVEL; 2001-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kevin M  Monson → RIVERSIDE SAND & GRAVEL; 2001-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kevin M  Monson → Riverside Sand & Gravel; 2001-05-01 to current/open; source msha-controller-operator-history