# Relationship history for MSHA mine 1700697

Current hierarchy: **Michael S  Copp → Copp Excavation Inc → Copp Excavation, Inc**

- 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:** Durgin Sand & Gravel Inc → Copp Excavation, Inc; 2000-10-01 to 2021-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Dennis  Durgin → Copp Excavation, Inc; 2000-10-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dennis  Durgin → Durgin Sand & Gravel Inc; 2000-10-01 to 2021-05-31; source msha-controller-operator-history
- **controller_controls_mine:** Michael S  Copp → Copp Excavation, Inc; 2006-11-08 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Copp Excavation Inc → Copp Excavation, Inc; 2021-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Michael S  Copp → Copp Excavation Inc; 2021-06-01 to current/open; source msha-controller-operator-history