# Relationship history for MSHA mine 2103914

Current hierarchy: **James  Durfee; Alice  Durfee → Dirt Work Specialists LLC → Astec Plant**

- 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:** Dirt Work Specialists LLC → Astec Plant; 2017-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Alice  Durfee et al → Astec Plant; 2017-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Alice  Durfee et al → Dirt Work Specialists LLC; 2017-07-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James  Durfee et al → Dirt Work Specialists LLC; 2017-07-20 to current/open; source msha-controller-operator-history