# Relationship history for MSHA mine 4703457

Current hierarchy: **Patrick  Strachan → Evenson Construction Company Inc. → Powerscreen Plant**

- 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

- **controller_controls_mine:** Eric  Gilbert → Powerscreen Plant; 1950-01-01 to 2014-12-23; source msha-controller-operator-history
- **controller_controls_mine:** Patrick  Strachan → Powerscreen Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cedar Lake Sand & Gravel Co. Inc. → Powerscreen Plant; 2006-05-16 to 2016-02-23; source msha-controller-operator-history
- **controller_controls_operator:** Eric  Gilbert → Cedar Lake Sand & Gravel Co. Inc.; 2006-05-16 to 2014-12-23; source msha-controller-operator-history
- **controller_controls_mine:** Patrick J  Strachan et al → Powerscreen Plant; 2014-12-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick J  Strachan et al → Cedar Lake Sand & Gravel Co. Inc.; 2014-12-24 to 2016-02-23; source msha-controller-operator-history
- **controller_controls_operator:** James  Gilbert et al → Cedar Lake Sand & Gravel Co. Inc.; 2014-12-24 to 2016-02-23; source msha-controller-operator-history
- **operator_operates_mine:** Evenson Construction Company Inc. → Powerscreen Plant; 2016-02-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick  Strachan → Evenson Construction Company Inc.; 2016-02-24 to current/open; source msha-controller-operator-history