# Relationship history for MSHA mine 0301631

Current hierarchy: **Harold  Lancaster → Stone County Material Inc → Portable Crusher #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

- **operator_operates_mine:** Stone County Material Inc → Portable Crusher #1; 1987-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Harold  Lancaster → Portable Crusher #1; 1987-07-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Harold  Lancaster → Stone County Material Inc; 1987-07-01 to current/open; source msha-controller-operator-history