# Relationship history for MSHA mine 4201895

Current hierarchy: **Massey Adam L → Warhawk Enterprise Inc → Old Slaugh Gravel Pit**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Skewes & Hamilton Construction Inc → Old Slaugh Gravel Pit; 1984-08-01 to 1985-10-28; source msha-controller-operator-history
- **controller_controls_mine:** Hamilton Lynn F → Old Slaugh Gravel Pit; 1984-08-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Hamilton Lynn F → Skewes & Hamilton Construction Inc; 1984-08-01 to 1985-10-28; source msha-controller-operator-history
- **operator_operates_mine:** Horseshoe Bend Sand & Gravel → Old Slaugh Gravel Pit; 1985-10-29 to 1987-12-30; source msha-controller-operator-history
- **controller_controls_mine:** Massey Norman & Edwin → Old Slaugh Gravel Pit; 1985-10-29 to 1987-12-30; source msha-controller-operator-history
- **controller_controls_operator:** Massey Norman & Edwin → Horseshoe Bend Sand & Gravel; 1985-10-29 to 1987-12-30; source msha-controller-operator-history
- **operator_operates_mine:** Warhawk Enterprise Inc → Old Slaugh Gravel Pit; 1987-12-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Massey Adam L → Old Slaugh Gravel Pit; 1987-12-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Massey Adam L → Warhawk Enterprise Inc; 1987-12-31 to current/open; source msha-controller-operator-history