# Relationship history for MSHA mine 0405315

Current hierarchy: **Scott L  Ritchie; Erik M  Cordova → San Diego Mining Company → HERCULES 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

- **operator_operates_mine:** San Diego Mining Company → HERCULES MINE; 1997-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Erik M  Cordova Et Al → HERCULES MINE; 1997-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Erik M  Cordova Et Al → San Diego Mining Company; 1997-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Scott L  Ritchie Et Al → San Diego Mining Company; 1997-06-01 to current/open; source msha-controller-operator-history