# Relationship history for MSHA mine 1901257

Current hierarchy: **Joseph A  Arruda → BRS Inc → River Rock Materials**

- 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:** Daniel G  Kirker et al → River Rock Materials; 1998-03-26 to 2015-10-25; source msha-controller-operator-history
- **operator_operates_mine:** BRS Inc → River Rock Materials; 2015-10-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joseph A  Arruda → River Rock Materials; 2015-10-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joseph A  Arruda → BRS Inc; 2015-10-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Daniel G  Kirker et al → BRS Inc; 2015-10-26 to 2015-10-25; source msha-controller-operator-history
- **controller_controls_operator:** Joseph A  Arruda et al → BRS Inc; 2015-10-26 to 2015-10-25; source msha-controller-operator-history