# Relationship history for MSHA mine 0202187

Current hierarchy: **Mc Elwain Carol → Flag Rock Inc → Portable 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:** Kelton Edward S → Portable Crusher #1; 1950-01-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Edward S Kelton Contracting Company Inc → Portable Crusher #1; 1983-12-01 to 1988-06-14; source msha-controller-operator-history
- **controller_controls_operator:** Kelton Edward S → Edward S Kelton Contracting Company Inc; 1983-12-01 to 1988-06-14; source msha-controller-operator-history
- **operator_operates_mine:** Flag Rock Inc → Portable Crusher #1; 1988-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Mc Elwain Carol → Portable Crusher #1; 1988-06-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Mc Elwain Carol → Flag Rock Inc; 1988-06-15 to current/open; source msha-controller-operator-history