# Relationship history for MSHA mine 3304560

Current hierarchy: **Benjamin  Geddis; Steve R  Oliver → Cornerstone Crushing, LLC → Walhonding Valley Sand & Gravel Co.**

- 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:** Walhonding Valley Sand & Gravel Co. → Walhonding Valley Sand & Gravel Co.; 2006-01-03 to 2023-07-02; source msha-controller-operator-history
- **controller_controls_mine:** Ezra J  Helmick → Walhonding Valley Sand & Gravel Co.; 2006-01-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ezra J  Helmick → Walhonding Valley Sand & Gravel Co.; 2006-01-03 to 2023-07-02; source msha-controller-operator-history
- **controller_controls_mine:** Benjamin  Geddis et al → Walhonding Valley Sand & Gravel Co.; 2017-02-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cornerstone Crushing, LLC → Walhonding Valley Sand & Gravel Co.; 2023-07-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Benjamin  Geddis et al → Cornerstone Crushing, LLC; 2023-07-03 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Steve R  Oliver et al → Cornerstone Crushing, LLC; 2023-07-03 to current/open; source msha-controller-operator-history