# Relationship history for MSHA mine 1001911

Current hierarchy: **Robert W  Blewett → Highland Enterprises LLC → Mt Solo Pit**

- 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:** Highland Enterprises Inc → Mt Solo Pit; 1995-03-01 to 2006-02-04; source msha-controller-operator-history
- **controller_controls_mine:** Robert W  Blewett et al → Mt Solo Pit; 1995-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert W  Blewett et al → Highland Enterprises Inc; 1995-03-01 to 2006-02-04; source msha-controller-operator-history
- **operator_operates_mine:** Highland Enterprises LLC → Mt Solo Pit; 2006-02-05 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert W  Blewett et al → Mt Solo Pit; 2006-02-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert W  Blewett et al → Highland Enterprises LLC; 2006-02-15 to current/open; source msha-controller-operator-history