# Relationship history for MSHA mine 0505191

Current hierarchy: **Burnco Rock Products Ltd → Burnco → Ewing Gravel 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

- **controller_controls_mine:** Bret  Hall et al → Ewing Gravel Pit; 2009-02-13 to 2017-02-26; source msha-controller-operator-history
- **controller_controls_mine:** Burnco Rock Products Ltd → Ewing Gravel Pit; 2017-02-27 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Burnco → Ewing Gravel Pit; 2024-05-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bret  Hall et al → Burnco; 2024-05-07 to 2017-02-26; source msha-controller-operator-history
- **controller_controls_operator:** Scott  Masi et al → Burnco; 2024-05-07 to 2017-02-26; source msha-controller-operator-history
- **controller_controls_operator:** Burnco Rock Products Ltd → Burnco; 2024-05-07 to current/open; source msha-controller-operator-history