# Relationship history for MSHA mine 4503770

Current hierarchy: **Eben  Twaddle → Interwest Construction Inc. → Elwha Gravel 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Eben  Twaddle → Elwha Gravel Pit; 2016-01-20 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** North Hill Resources → Elwha Gravel Pit; 2017-03-21 to 2018-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Sean  McGuiness → Elwha Gravel Pit; 2017-03-21 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sean  McGuiness → North Hill Resources; 2017-03-21 to 2018-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Interwest Construction Inc. → Elwha Gravel Pit; 2019-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eben  Twaddle → Interwest Construction Inc.; 2019-01-01 to current/open; source msha-controller-operator-history