# Relationship history for MSHA mine 3606107

Current hierarchy: **Dennis K  Snyder II → Snyder Coal Company → 7 Ft Slope Mine**

- 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:** Snyder Coal Company → 7 Ft Slope Mine; 1976-10-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dennis  Snyder → 7 Ft Slope Mine; 1976-10-23 to 2005-08-31; source msha-controller-operator-history
- **controller_controls_operator:** Dennis  Snyder → Snyder Coal Company; 1976-10-23 to 2005-08-31; source msha-controller-operator-history
- **controller_controls_mine:** Dennis K  Snyder II → 7 Ft Slope Mine; 2005-09-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Dennis K  Snyder II → Snyder Coal Company; 2005-09-01 to current/open; source msha-controller-operator-history