# Relationship history for MSHA mine 1515899

Current hierarchy: **B W  McDonald → Fast Track Production Inc → Mine #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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Fast Track Production Inc → Mine #1; 1987-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** B W  McDonald → Mine #1; 1987-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** B W  McDonald → Fast Track Production Inc; 1987-01-01 to current/open; source msha-controller-operator-history