# Relationship history for MSHA mine 3503499

Current hierarchy: **Richard  Pearsall → Cascade Pumice Inc → Johnson Rd Mine**

- 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

- **controller_controls_mine:** Richard  Pearsall → Johnson Rd Mine; 1994-10-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Cascade Pumice Inc → Johnson Rd Mine; 2000-05-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Richard  Pearsall → Cascade Pumice Inc; 2000-05-01 to current/open; source msha-controller-operator-history