# Relationship history for MSHA mine 0102681

Current hierarchy: **Johnson Earl → Century Gravel Company → Century 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Johnson Earl → Century Gravel; 1980-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Century Gravel Company → Century Gravel; 1986-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Johnson Earl → Century Gravel Company; 1986-05-01 to current/open; source msha-controller-operator-history