# Relationship history for MSHA mine 2902177

Current hierarchy: **Bruce  Jassmann → Bruces Gravel → SCREEN PLANT #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:** Golden Talon → SCREEN PLANT #1; 1998-07-01 to 2001-02-28; source msha-controller-operator-history
- **controller_controls_mine:** Alfonso  Vigil → SCREEN PLANT #1; 1998-07-01 to 2001-02-28; source msha-controller-operator-history
- **controller_controls_operator:** Alfonso  Vigil → Golden Talon; 1998-07-01 to 2001-02-28; source msha-controller-operator-history
- **operator_operates_mine:** Bruces Gravel → SCREEN PLANT #1; 2001-03-01 to 2008-12-31; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Jassmann → SCREEN PLANT #1; 2001-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Jassmann → Bruces Gravel; 2001-03-01 to 2008-12-31; source msha-controller-operator-history
- **operator_operates_mine:** Bruces Gravel → SCREEN PLANT #1; 2009-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bruce  Jassmann → SCREEN PLANT #1; 2009-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bruce  Jassmann → Bruces Gravel; 2009-01-01 to current/open; source msha-controller-operator-history