# Relationship history for MSHA mine 2402540

Current hierarchy: **Mark  Runkle; Greg  Dahl → R & D Partners LLC → Portable Screening Plant**

- 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

- **operator_operates_mine:** R & D Partners LLC → Portable Screening Plant; 2008-11-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mark  Runkle et al → Portable Screening Plant; 2008-11-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mark  Runkle et al → R & D Partners LLC; 2008-11-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Greg  Dahl et al → R & D Partners LLC; 2008-11-17 to current/open; source msha-controller-operator-history