# Relationship history for MSHA mine 2501177

Current hierarchy: **Lyndsey K Hasenkamp; Kandice Karen McCoy; Taron L Hasenkamp; Roger  McCo → M&H Sand&Gravel LLC → M&H Sand &Gravel LLC**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-18T09:31:49.615908+00:00

## Valid-time edges

- **operator_operates_mine:** Gary Backhaus Gravel → M&H Sand &Gravel LLC; 1998-04-01 to 2021-06-15; source msha-controller-operator-history
- **controller_controls_mine:** Gary  Backhaus → M&H Sand &Gravel LLC; 1998-04-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary  Backhaus → Gary Backhaus Gravel; 1998-04-01 to 2021-06-15; source msha-controller-operator-history
- **operator_operates_mine:** Gary Backhaus Gravel LLC → M&H Sand &Gravel LLC; 2021-06-16 to 2025-07-22; source msha-controller-operator-history
- **controller_controls_mine:** Gary  Backhaus → M&H Sand &Gravel LLC; 2021-06-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Gary  Backhaus → Gary Backhaus Gravel LLC; 2021-06-16 to 2025-07-22; source msha-controller-operator-history
- **operator_operates_mine:** M&H Sand&Gravel LLC → M&H Sand &Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Taron L Hasenkamp et al → M&H Sand &Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Taron L Hasenkamp et al → M&H Sand&Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kandice Karen McCoy et al → M&H Sand&Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roger  McCoy et al → M&H Sand&Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Lyndsey K Hasenkamp et al → M&H Sand&Gravel LLC; 2025-07-23 to current/open; source msha-controller-operator-history