# Relationship history for MSHA mine 0404809

Current hierarchy: **Eierman Conrad R → Desert Gold Inc → N C 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:** Lawrence Sapp → N C Gravel; 1986-05-01 to 1989-10-25; source msha-controller-operator-history
- **controller_controls_mine:** Lawrence L  Sapp → N C Gravel; 1986-05-01 to 1989-10-25; source msha-controller-operator-history
- **controller_controls_operator:** Lawrence L  Sapp → Lawrence Sapp; 1986-05-01 to 1989-10-25; source msha-controller-operator-history
- **operator_operates_mine:** Desert Gold Inc → N C Gravel; 1989-10-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Eierman Conrad R → N C Gravel; 1989-10-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Eierman Conrad R → Desert Gold Inc; 1989-10-26 to current/open; source msha-controller-operator-history