# Relationship history for MSHA mine 3001585

Current hierarchy: **Lawrence  Huff → L L Huff Co Inc → Monarch 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:** V J Damico Inc → Monarch Sand & Gravel; 1950-01-01 to 1999-05-24; source msha-controller-operator-history
- **controller_controls_mine:** Vincent J  Damico → Monarch Sand & Gravel; 1950-01-01 to 1999-05-24; source msha-controller-operator-history
- **controller_controls_operator:** Vincent J  Damico → V J Damico Inc; 1950-01-01 to 1999-05-24; source msha-controller-operator-history
- **operator_operates_mine:** L L Huff Co Inc → Monarch Sand & Gravel; 1999-05-25 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Lawrence  Huff → Monarch Sand & Gravel; 1999-05-25 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lawrence  Huff → L L Huff Co Inc; 1999-05-25 to current/open; source msha-controller-operator-history