# Relationship history for MSHA mine 2602494

Current hierarchy: **Steve W  Klomp → Advanced Pozzolan Products LLC → Advanced Pozzolan Products LLC**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Natural Pozzolan of Nevada LLC → Advanced Pozzolan Products LLC; 2002-04-22 to 2007-09-13; source msha-controller-operator-history
- **controller_controls_mine:** Robert L Laird et al → Advanced Pozzolan Products LLC; 2002-04-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert L Laird et al → Natural Pozzolan of Nevada LLC; 2002-04-22 to 2007-09-13; source msha-controller-operator-history
- **operator_operates_mine:** Advanced Pozzolan Products LLC → Advanced Pozzolan Products LLC; 2007-09-14 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Steve W  Klomp  et al → Advanced Pozzolan Products LLC; 2007-09-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve W  Klomp  et al → Advanced Pozzolan Products LLC; 2007-09-14 to current/open; source msha-controller-operator-history