# Relationship history for MSHA mine 2501142

Current hierarchy: **Jarett L  Doernemann → Elkhorn Valley Sand & Gravel → Elkhorn Valley Sand & Gravel**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Quality Sand & Gravel, Inc. → Elkhorn Valley Sand & Gravel; 1992-08-01 to 2006-07-16; source msha-controller-operator-history
- **controller_controls_mine:** Elwood G  Meredith → Elkhorn Valley Sand & Gravel; 1992-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Elwood G  Meredith → Quality Sand & Gravel, Inc.; 1992-08-01 to 2006-07-16; source msha-controller-operator-history
- **operator_operates_mine:** Elkhorn Valley Sand & Gravel → Elkhorn Valley Sand & Gravel; 2006-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Jarett L  Doernemann  et al → Elkhorn Valley Sand & Gravel; 2006-07-17 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Jarett L  Doernemann  et al → Elkhorn Valley Sand & Gravel; 2006-07-17 to current/open; source msha-controller-operator-history