# Relationship history for MSHA mine 0201927

Current hierarchy: **Breen Dennis → Pueblo Sand & Gravel Inc → Pueblo Pebbles 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

- **operator_operates_mine:** Pueblo Pebbles Inc → Pueblo Pebbles Pit; 1979-01-01 to 1983-05-17; source msha-controller-operator-history
- **controller_controls_mine:** Portell Leonard A → Pueblo Pebbles Pit; 1979-01-01 to 1983-05-17; source msha-controller-operator-history
- **controller_controls_operator:** Portell Leonard A → Pueblo Pebbles Inc; 1979-01-01 to 1983-05-17; source msha-controller-operator-history
- **operator_operates_mine:** Pueblo Sand & Gravel Inc → Pueblo Pebbles Pit; 1983-05-18 to 1986-10-07; source msha-controller-operator-history
- **controller_controls_mine:** Bright Charles → Pueblo Pebbles Pit; 1983-05-18 to 1986-10-07; source msha-controller-operator-history
- **controller_controls_operator:** Bright Charles → Pueblo Sand & Gravel Inc; 1983-05-18 to 1986-10-07; source msha-controller-operator-history
- **operator_operates_mine:** Pueblo Sand & Gravel Inc → Pueblo Pebbles Pit; 1986-10-08 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Breen Dennis → Pueblo Pebbles Pit; 1986-10-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Breen Dennis → Pueblo Sand & Gravel Inc; 1986-10-08 to current/open; source msha-controller-operator-history