# Relationship history for MSHA mine 1518981

Current hierarchy: **Randall  Wagers → Sandhill Processing Coal Co. → Green Haul #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

- **controller_controls_mine:** Randall  Wagers et al → Green Haul #1; 1992-03-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Sandhill Processing Coal Co. → Green Haul #1; 2006-03-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Randall  Wagers et al → Sandhill Processing Coal Co.; 2006-03-27 to current/open; source msha-controller-operator-history