# Relationship history for MSHA mine 1601532

Current hierarchy: **Trisha  Duncan; Patrick  Ryder → Brownstone Sand and Gravel Inc → Knight 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

- **controller_controls_mine:** Shane  Cambre et al → Knight Pit; 2011-03-15 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Enon Sand and Gravel LLC → Knight Pit; 2013-09-25 to 2018-12-03; source msha-controller-operator-history
- **controller_controls_operator:** Shane  Cambre et al → Enon Sand and Gravel LLC; 2013-09-25 to 2018-12-03; source msha-controller-operator-history
- **controller_controls_operator:** Glynn  Huhn et al → Enon Sand and Gravel LLC; 2013-09-25 to 2018-12-03; source msha-controller-operator-history
- **operator_operates_mine:** Brownstone Sand and Gravel Inc → Knight Pit; 2018-12-04 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brent  Kovach et al → Knight Pit; 2018-12-04 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Brent  Kovach et al → Brownstone Sand and Gravel Inc; 2018-12-04 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_operator:** M Shawn  Krantz et al → Brownstone Sand and Gravel Inc; 2018-12-04 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_operator:** Joseph  Shaw et al → Brownstone Sand and Gravel Inc; 2018-12-04 to 2025-08-03; source msha-controller-operator-history
- **controller_controls_mine:** Trisha  Duncan et al → Knight Pit; 2025-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Trisha  Duncan et al → Brownstone Sand and Gravel Inc; 2025-08-04 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Patrick  Ryder et al → Brownstone Sand and Gravel Inc; 2025-08-04 to current/open; source msha-controller-operator-history