# Relationship history for MSHA mine 1401293

Current hierarchy: **Christopher J  Eichman → Midwest Concrete Materials, Inc. → Riley County Sand 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **controller_controls_mine:** Ashland Inc → Riley County Sand Plant; 1950-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert H  Eichman → Riley County Sand Plant; 1950-01-01 to 2025-01-31; source msha-controller-operator-history
- **operator_operates_mine:** Reno Construction Company → Riley County Sand Plant; 1978-12-01 to 1980-04-27; source msha-controller-operator-history
- **controller_controls_operator:** Ashland Inc → Reno Construction Company; 1978-12-01 to 1980-04-27; source msha-controller-operator-history
- **operator_operates_mine:** Shilling Sand & Gravel Inc → Riley County Sand Plant; 1980-04-28 to 1995-05-07; source msha-controller-operator-history
- **controller_controls_mine:** Michael D  Shilling → Riley County Sand Plant; 1980-04-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael D  Shilling → Shilling Sand & Gravel Inc; 1980-04-28 to 1995-05-07; source msha-controller-operator-history
- **operator_operates_mine:** Midwest Concrete Materials, Inc. → Riley County Sand Plant; 1995-05-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert H  Eichman → Midwest Concrete Materials, Inc.; 1995-05-08 to 2025-01-31; source msha-controller-operator-history
- **controller_controls_mine:** Christopher J  Eichman → Riley County Sand Plant; 2025-02-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Christopher J  Eichman → Midwest Concrete Materials, Inc.; 2025-02-01 to current/open; source msha-controller-operator-history