# Relationship history for MSHA mine 2902256

Current hierarchy: **Kelly  Armstrong → Copar Pumice Company Inc → South 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:** Kelly  Armstrong → South Pit; 1998-05-13 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Copar Pumice Company Inc → South Pit; 2003-10-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kelly  Armstrong → Copar Pumice Company Inc; 2003-10-06 to current/open; source msha-controller-operator-history