# Relationship history for MSHA mine 3901641

Current hierarchy: **Darrin  Brownlee; Rick  Brownlee → B&H CONTRACTORS OF SD → ELKTON PIT**

- 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:** B&H CONTRACTORS OF SD → ELKTON PIT; 2019-08-22 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Darrin  Brownlee et al → ELKTON PIT; 2019-08-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Darrin  Brownlee et al → B&H CONTRACTORS OF SD; 2019-08-22 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rick  Brownlee et al → B&H CONTRACTORS OF SD; 2019-08-22 to current/open; source msha-controller-operator-history