# Relationship history for MSHA mine 5100251

Current hierarchy: **Sanford  Ota → SAN Construction LLC → 638 TPH Extec Portable Crusher**

- 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:** Kajima International Inc → 638 TPH Extec Portable Crusher; 2005-04-14 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Hawaiian Dredging Construction Company → 638 TPH Extec Portable Crusher; 2005-04-15 to 2006-10-29; source msha-controller-operator-history
- **controller_controls_operator:** Kajima International Inc → Hawaiian Dredging Construction Company; 2005-04-15 to 2006-10-29; source msha-controller-operator-history
- **operator_operates_mine:** SAN Construction LLC → 638 TPH Extec Portable Crusher; 2006-10-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Sanford  Ota et al → 638 TPH Extec Portable Crusher; 2006-10-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sanford  Ota et al → SAN Construction LLC; 2006-10-30 to current/open; source msha-controller-operator-history