# Relationship history for MSHA mine 2602614

Current hierarchy: **Roy  Christiansen; Keith  Carson → CPS Rock & Sand Inc → Cross Timbers 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:** CPS Rock & Sand Inc → Cross Timbers Pit; 2007-06-27 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Roy  Christiansen  et al → Cross Timbers Pit; 2007-06-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Roy  Christiansen  et al → CPS Rock & Sand Inc; 2007-06-27 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Keith  Carson  et al → CPS Rock & Sand Inc; 2007-06-27 to current/open; source msha-controller-operator-history