# Relationship history for MSHA mine 4503630

Current hierarchy: **Sandra  Forman → Pacific Topsoils, Inc. → Port P-91 4242 Re-Circulating Impactor**

- 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:** Pacific Topsoils, Inc. → Port P-91 4242 Re-Circulating Impactor; 2007-04-23 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Dave  Forman → Port P-91 4242 Re-Circulating Impactor; 2007-04-23 to 2013-04-15; source msha-controller-operator-history
- **controller_controls_operator:** Dave  Forman → Pacific Topsoils, Inc.; 2007-04-23 to 2013-04-15; source msha-controller-operator-history
- **controller_controls_mine:** Sandra  Forman → Port P-91 4242 Re-Circulating Impactor; 2013-04-16 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Sandra  Forman → Pacific Topsoils, Inc.; 2013-04-16 to current/open; source msha-controller-operator-history