# Relationship history for MSHA mine 5100217

Current hierarchy: **Kajima International Inc → Hawaiian Dredging Construction Company → 1500 TPH Portable Stone Quarry**

- 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:** Hawaiian Dredging Construction Company → 1500 TPH Portable Stone Quarry; 1992-12-01 to 2005-04-13; source msha-controller-operator-history
- **controller_controls_mine:** Dillingham Construction Corp → 1500 TPH Portable Stone Quarry; 1992-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dillingham Construction Corp → Hawaiian Dredging Construction Company; 1992-12-01 to 2005-04-13; source msha-controller-operator-history
- **operator_operates_mine:** Hawaiian Dredging Construction Company → 1500 TPH Portable Stone Quarry; 2005-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kajima International Inc → 1500 TPH Portable Stone Quarry; 2005-04-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kajima International Inc → Hawaiian Dredging Construction Company; 2005-04-14 to current/open; source msha-controller-operator-history