# Relationship history for MSHA mine 1400464

Current hierarchy: **Robert K  Lauer; Richard H  Kistner → Blue River Sand & Gravel → Blue River 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Blue River Sand & Gravel Company → Blue River Sand & Gravel; 1950-01-01 to 1986-10-15; source msha-controller-operator-history
- **controller_controls_mine:** Floyd J  Stryker → Blue River Sand & Gravel; 1950-01-01 to 1986-10-15; source msha-controller-operator-history
- **controller_controls_operator:** Floyd J  Stryker → Blue River Sand & Gravel Company; 1950-01-01 to 1986-10-15; source msha-controller-operator-history
- **controller_controls_mine:** Richard H  Kistner → Blue River Sand & Gravel; 1986-02-01 to 2019-04-09; source msha-controller-operator-history
- **operator_operates_mine:** Blue River Sand & Gravel → Blue River Sand & Gravel; 1986-10-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard H  Kistner → Blue River Sand & Gravel; 1986-10-16 to 2019-04-09; source msha-controller-operator-history
- **controller_controls_mine:** Richard H  Kistner et al → Blue River Sand & Gravel; 2019-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard H  Kistner et al → Blue River Sand & Gravel; 2019-04-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert K  Lauer et al → Blue River Sand & Gravel; 2019-04-10 to current/open; source msha-controller-operator-history