# Relationship history for MSHA mine 2602430

Current hierarchy: **Kent  Fitch → American Silica Inc → Crusher #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

- **controller_controls_mine:** Neil R  Zoller → Crusher #1; 1996-07-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Tri-States Rock & Mineral Inc → Crusher #1; 2000-08-01 to 2001-09-05; source msha-controller-operator-history
- **controller_controls_operator:** Neil R  Zoller → Tri-States Rock & Mineral Inc; 2000-08-01 to 2001-09-05; source msha-controller-operator-history
- **operator_operates_mine:** American Silica Inc → Crusher #1; 2001-09-06 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Kent  Fitch → Crusher #1; 2001-09-06 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Kent  Fitch → American Silica Inc; 2001-09-06 to current/open; source msha-controller-operator-history