# Relationship history for MSHA mine 1601612

Current hierarchy: **Marcus L Dyess → Superior Sand and Gravel → Plant 3**

- 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:** Eric  Johnson → Plant 3; 2019-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Marcus L Dyess → Plant 3; 2020-09-23 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Highland Rock Company, Inc. → Plant 3; 2022-06-24 to 2022-09-13; source msha-controller-operator-history
- **controller_controls_operator:** Eric  Johnson → Highland Rock Company, Inc.; 2022-06-24 to 2022-09-13; source msha-controller-operator-history
- **operator_operates_mine:** Superior Sand and Gravel → Plant 3; 2022-09-14 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Marcus L Dyess → Superior Sand and Gravel; 2022-09-14 to current/open; source msha-controller-operator-history