# Relationship history for MSHA mine 3608061

Current hierarchy: **Bill T  Johnson → Stevensville Stone Supply LLC → Stevensville Stone Supply 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: 2026-10-13T11:19:05.459773+00:00

## Valid-time edges

- **operator_operates_mine:** Bill Johnson Quarry → Stevensville Stone Supply LLC; 1988-12-01 to 2018-10-27; source msha-controller-operator-history
- **controller_controls_mine:** Bill T  Johnson → Stevensville Stone Supply LLC; 1988-12-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bill T  Johnson → Bill Johnson Quarry; 1988-12-01 to 2018-10-27; source msha-controller-operator-history
- **operator_operates_mine:** Stevensville Stone Supply LLC → Stevensville Stone Supply LLC; 2018-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Bill T  Johnson → Stevensville Stone Supply LLC; 2018-10-28 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Bill T  Johnson → Stevensville Stone Supply LLC; 2018-10-28 to current/open; source msha-controller-operator-history