# Relationship history for MSHA mine 3608310

Current hierarchy: **Drebitko Andrew → Mountain Valley Management Inc → Buck Strip**

- 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:** Mountain Valley Management Inc → Buck Strip; 1991-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Drebitko Andrew → Buck Strip; 1991-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Drebitko Andrew → Mountain Valley Management Inc; 1991-12-01 to current/open; source msha-controller-operator-history