# Relationship history for MSHA mine 1202171

Current hierarchy: **Jack  Salts → Salts Sand & Gravel → Salts 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Triangle Gravel Inc → Salts Sand & Gravel; 1994-12-01 to 1999-10-27; source msha-controller-operator-history
- **controller_controls_mine:** Karen  O'Neil → Salts Sand & Gravel; 1994-12-01 to 1999-10-27; source msha-controller-operator-history
- **controller_controls_operator:** Karen  O'Neil → Triangle Gravel Inc; 1994-12-01 to 1999-10-27; source msha-controller-operator-history
- **operator_operates_mine:** Salts Sand & Gravel → Salts Sand & Gravel; 1999-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jack  Salts → Salts Sand & Gravel; 1999-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jack  Salts → Salts Sand & Gravel; 1999-10-28 to current/open; source msha-controller-operator-history