# Relationship history for MSHA mine 0201885

Current hierarchy: **Graham Willie G → Arizona Cinder Company → Sheep Hill**

- Valid-time bounds: inclusive, date granularity
- Null end: open-ended in the upstream history row; not independent proof of present control
- Transaction-time observation: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** Garwalt Enterprises Inc → Sheep Hill; 1978-03-09 to 1982-10-20; source msha-controller-operator-history
- **controller_controls_mine:** Walters David C & Garlin Glaspie → Sheep Hill; 1978-03-09 to 1982-10-20; source msha-controller-operator-history
- **controller_controls_operator:** Walters David C & Garlin Glaspie → Garwalt Enterprises Inc; 1978-03-09 to 1982-10-20; source msha-controller-operator-history
- **operator_operates_mine:** Arizona Cinders Inc → Sheep Hill; 1982-10-21 to 1984-06-12; source msha-controller-operator-history
- **controller_controls_mine:** Walters David C-Larry Reed Et Al → Sheep Hill; 1982-10-21 to 1984-06-12; source msha-controller-operator-history
- **controller_controls_operator:** Walters David C-Larry Reed Et Al → Arizona Cinders Inc; 1982-10-21 to 1984-06-12; source msha-controller-operator-history
- **operator_operates_mine:** Arizona Cinder Company → Sheep Hill; 1984-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Graham Willie G → Sheep Hill; 1984-06-13 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Graham Willie G → Arizona Cinder Company; 1984-06-13 to current/open; source msha-controller-operator-history