# Relationship history for MSHA mine 2501077

Current hierarchy: **York County - Ne → York County Highway Department → PORTABLE DREDGE #4/LUX 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:** Vayden  Anderson et al → PORTABLE DREDGE #4/LUX PIT; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** York County Highway Department → PORTABLE DREDGE #4/LUX PIT; 1987-03-01 to 1991-07-16; source msha-controller-operator-history
- **controller_controls_mine:** York County - Ne → PORTABLE DREDGE #4/LUX PIT; 1987-03-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** York County - Ne → York County Highway Department; 1987-03-01 to 1991-07-16; source msha-controller-operator-history
- **operator_operates_mine:** Overland Sand & Gravel Company → PORTABLE DREDGE #4/LUX PIT; 1991-07-17 to 1994-06-06; source msha-controller-operator-history
- **controller_controls_operator:** Vayden  Anderson et al → Overland Sand & Gravel Company; 1991-07-17 to 1994-06-06; source msha-controller-operator-history
- **operator_operates_mine:** York County Highway Department → PORTABLE DREDGE #4/LUX PIT; 1994-06-07 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** York County - Ne → York County Highway Department; 1994-06-07 to current/open; source msha-controller-operator-history