# Relationship history for MSHA mine 1601324

Current hierarchy: **Bryan L  Bossier Sr → Diamond B Construction Co., LLC → Isabel Rockcrusher**

- 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

- **controller_controls_mine:** Bryan L  Bossier Sr → Isabel Rockcrusher; 1993-08-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Covington Paving Company Inc → Isabel Rockcrusher; 1997-12-01 to 2009-09-17; source msha-controller-operator-history
- **controller_controls_mine:** Richard U  Core  et al → Isabel Rockcrusher; 1997-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard U  Core  et al → Covington Paving Company Inc; 1997-12-01 to 2009-09-17; source msha-controller-operator-history
- **controller_controls_operator:** James L  Core  et al → Covington Paving Company Inc; 1997-12-01 to 2009-09-17; source msha-controller-operator-history
- **operator_operates_mine:** Diamond B Construction Co LLC → Isabel Rockcrusher; 2009-09-18 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bryan L  Bossier Sr → Diamond B Construction Co LLC; 2009-09-18 to current/open; source msha-controller-operator-history