# Relationship history for MSHA mine 2200600

Current hierarchy: **Terrell A Newell → Newell Sand & Gravel → Newell 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

- **controller_controls_mine:** Charles D  McKay → Newell Sand & Gravel; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mc Kay Sand & Gravel → Newell Sand & Gravel; 1987-08-01 to 1989-08-07; source msha-controller-operator-history
- **controller_controls_operator:** Charles D  McKay → Mc Kay Sand & Gravel; 1987-08-01 to 1989-08-07; source msha-controller-operator-history
- **operator_operates_mine:** Newell Sand & Gravel → Newell Sand & Gravel; 1989-08-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Terrell A Newell → Newell Sand & Gravel; 1989-08-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Terrell A Newell → Newell Sand & Gravel; 1989-08-08 to current/open; source msha-controller-operator-history