# Relationship history for MSHA mine 0502898

Current hierarchy: **Cyprus Amax Minerals Company → Cyprus Orchard Valley Coal Corp → Cyprus Orchard Valley**

- 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:** Colorado Westmoreland Inc → Cyprus Orchard Valley; 1976-01-01 to 1988-11-29; source msha-controller-operator-history
- **controller_controls_mine:** Westmoreland Coal Company → Cyprus Orchard Valley; 1976-01-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Westmoreland Coal Company → Colorado Westmoreland Inc; 1976-01-01 to 1988-11-29; source msha-controller-operator-history
- **operator_operates_mine:** Cyprus Orchard Valley Coal Corp → Cyprus Orchard Valley; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Cyprus Amax Minerals Company → Cyprus Orchard Valley; 1988-11-30 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Cyprus Amax Minerals Company → Cyprus Orchard Valley Coal Corp; 1988-11-30 to current/open; source msha-controller-operator-history