# Relationship history for MSHA mine 2102990

Current hierarchy: **Braum Michael  Elton → Elton Gravel, LLC → Portable 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Elton Gravel → Portable Plant #1; 1989-05-01 to 2012-03-19; source msha-controller-operator-history
- **controller_controls_mine:** Timothy J  Elton  et al → Portable Plant #1; 1989-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Timothy J  Elton  et al → Elton Gravel; 1989-05-01 to 2012-03-19; source msha-controller-operator-history
- **controller_controls_operator:** Lee E  Elton  et al → Elton Gravel; 1989-05-01 to 2012-03-19; source msha-controller-operator-history
- **operator_operates_mine:** Elton Gravel, LLC → Portable Plant #1; 2012-03-20 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Braum Michael  Elton → Portable Plant #1; 2012-03-20 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Braum Michael  Elton → Elton Gravel, LLC; 2012-03-20 to current/open; source msha-controller-operator-history