# Relationship history for MSHA mine 0202791

Current hierarchy: **Julie A Chaffin → Damavand Trading LLC → Rio Grande Material**

- 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:** Joseph F  Guinn et al → Rio Grande Material; 1983-09-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Ajax Contracting Company Inc → Rio Grande Material; 1998-10-01 to 2005-04-25; source msha-controller-operator-history
- **controller_controls_operator:** Joseph F  Guinn et al → Ajax Contracting Company Inc; 1998-10-01 to 2005-04-25; source msha-controller-operator-history
- **controller_controls_operator:** Woodrow J  Whitehurst et al → Ajax Contracting Company Inc; 1998-10-01 to 2005-04-25; source msha-controller-operator-history
- **operator_operates_mine:** Damavand Trading LLC → Rio Grande Material; 2005-04-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Julie A Chaffin et al → Rio Grande Material; 2005-04-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Julie A Chaffin et al → Damavand Trading LLC; 2005-04-26 to current/open; source msha-controller-operator-history