# Relationship history for MSHA mine 3301683

Current hierarchy: **Love Tom → Coprolite Sand & Gravel Corp → Coprolite Sand & Gravel Corp Devola Plan**

- 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:** Union Slag Corp → Coprolite Sand & Gravel Corp Devola Plan; 1950-01-01 to 1985-07-22; source msha-controller-operator-history
- **controller_controls_mine:** Calvin Harley E Et Al → Coprolite Sand & Gravel Corp Devola Plan; 1950-01-01 to 1985-07-22; source msha-controller-operator-history
- **controller_controls_operator:** Calvin Harley E Et Al → Union Slag Corp; 1950-01-01 to 1985-07-22; source msha-controller-operator-history
- **operator_operates_mine:** Union Slag Corp → Coprolite Sand & Gravel Corp Devola Plan; 1985-07-23 to 1992-03-09; source msha-controller-operator-history
- **controller_controls_mine:** Hune Josephine → Coprolite Sand & Gravel Corp Devola Plan; 1985-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hune Josephine → Union Slag Corp; 1985-07-23 to 1992-03-09; source msha-controller-operator-history
- **operator_operates_mine:** Coprolite Sand & Gravel Corp → Coprolite Sand & Gravel Corp Devola Plan; 1992-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Love Tom → Coprolite Sand & Gravel Corp Devola Plan; 1992-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Love Tom → Coprolite Sand & Gravel Corp; 1992-03-10 to current/open; source msha-controller-operator-history