# Relationship history for MSHA mine 5100220

Current hierarchy: **Hiram  Rivera → E.M. Rivera & Sons, Inc → Portable Plant - 5 (#1184)**

- 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:** West Oahu Aggregate Company Inc → Portable Plant - 5 (#1184); 1994-01-01 to 2006-11-28; source msha-controller-operator-history
- **controller_controls_mine:** Joaquin J  Silva et al → Portable Plant - 5 (#1184); 1994-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joaquin J  Silva et al → West Oahu Aggregate Company Inc; 1994-01-01 to 2006-11-28; source msha-controller-operator-history
- **controller_controls_operator:** Georgette  Silva et al → West Oahu Aggregate Company Inc; 1994-01-01 to 2006-11-28; source msha-controller-operator-history
- **controller_controls_mine:** Hiram  Rivera → Portable Plant - 5 (#1184); 2001-04-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** E.M. Rivera & Sons, Inc → Portable Plant - 5 (#1184); 2006-11-29 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hiram  Rivera → E.M. Rivera & Sons, Inc; 2006-11-29 to current/open; source msha-controller-operator-history