# Relationship history for MSHA mine 2001046

Current hierarchy: **Roland H  Huhtala → R H Huhtala Aggregates, 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:** R H Huhtala Construction → PORTABLE CRUSHER #1; 1950-01-01 to 2009-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Roland H  Huhtala → PORTABLE CRUSHER #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roland H  Huhtala → R H Huhtala Construction; 1950-01-01 to 2009-02-28; source msha-controller-operator-history
- **operator_operates_mine:** R H Huhtala Aggregates, Inc. → PORTABLE CRUSHER #1; 2009-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roland H  Huhtala → PORTABLE CRUSHER #1; 2009-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roland H  Huhtala → R H Huhtala Aggregates, Inc.; 2009-03-01 to current/open; source msha-controller-operator-history