# Relationship history for MSHA mine 1515227

Current hierarchy: **Brockman Jeff & William Mc Kinney → Gravel Lick Mining → No 1**

- 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:** Gravel Lick Mining → No 1; 1985-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Brockman Jeff & William Mc Kinney Et Al → No 1; 1985-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Brockman Jeff & William Mc Kinney Et Al → Gravel Lick Mining; 1985-05-01 to current/open; source msha-controller-operator-history