# Relationship history for MSHA mine 1901217

Current hierarchy: **Gilbert  Lopes → G. Lopes Construction, Inc. → PS-30 Chieftain**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Gilbert  Lopes et al → PS-30 Chieftain; 1994-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** G. Lopes Construction, Inc. → PS-30 Chieftain; 2012-02-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gilbert  Lopes et al → G. Lopes Construction, Inc.; 2012-02-16 to current/open; source msha-controller-operator-history