# Relationship history for MSHA mine 0600696

Current hierarchy: **Kenneth A  Burns → BC Sand & Gravel Co., Inc. → BC Sand & Gravel Co., Inc.**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **controller_controls_mine:** Kenneth A  Burns → BC Sand & Gravel Co., Inc.; 2001-06-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** BC Sand & Gravel Co., Inc. → BC Sand & Gravel Co., Inc.; 2001-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kenneth A  Burns → BC Sand & Gravel Co., Inc.; 2001-07-01 to current/open; source msha-controller-operator-history