# Relationship history for MSHA mine 1516815

Current hierarchy: **B W  McDonald → Blazing Saddles Coal Corp → Blazing Saddles Plant #1**

- 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:** B W  McDonald → Blazing Saddles Plant #1; 1983-06-06 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Blazing Saddles Coal Corp → Blazing Saddles Plant #1; 1990-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** B W  McDonald → Blazing Saddles Coal Corp; 1990-02-01 to current/open; source msha-controller-operator-history