# Relationship history for MSHA mine 3304732

Current hierarchy: **Ronnie L Welch; James R Welch → WELCH SAND & GRAVEL, INC → LOKOTRACK ST3.8**

- 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:** Charles H  Welch et al → LOKOTRACK ST3.8; 1950-01-01 to 2015-12-31; source msha-controller-operator-history
- **controller_controls_mine:** James R Welch et al → LOKOTRACK ST3.8; 2016-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** WELCH SAND & GRAVEL, INC → LOKOTRACK ST3.8; 2017-02-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James R Welch et al → WELCH SAND & GRAVEL, INC; 2017-02-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ronnie L Welch et al → WELCH SAND & GRAVEL, INC; 2017-02-24 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Charles H  Welch et al → WELCH SAND & GRAVEL, INC; 2017-02-24 to 2015-12-31; source msha-controller-operator-history