# Relationship history for MSHA mine 4503175

Current hierarchy: **James  Burnett; Lawrence P.  Hughes → Iron Mountain Quarry LLC → Iron Mountain Quarry**

- 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:** Iron Mountain Quarry LLC → Iron Mountain Quarry; 1988-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** James  Burnett et al → Iron Mountain Quarry; 1988-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James  Burnett et al → Iron Mountain Quarry LLC; 1988-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lawrence P.  Hughes et al → Iron Mountain Quarry LLC; 1988-08-01 to current/open; source msha-controller-operator-history