# Relationship history for MSHA mine 2002720

Current hierarchy: **Joel C  Barley → Barley Trucking & Excavating Inc → B-K 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:** D & M Materials Inc → B-K PIT; 1984-07-01 to 1993-06-27; source msha-controller-operator-history
- **controller_controls_mine:** Michael K  Brodzinski → B-K PIT; 1984-07-01 to 1993-06-27; source msha-controller-operator-history
- **controller_controls_operator:** Michael K  Brodzinski → D & M Materials Inc; 1984-07-01 to 1993-06-27; source msha-controller-operator-history
- **operator_operates_mine:** Barley Trucking & Excavating Inc → B-K PIT; 1993-06-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Joel C  Barley → B-K PIT; 1993-06-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Joel C  Barley → Barley Trucking & Excavating Inc; 1993-06-28 to current/open; source msha-controller-operator-history