# Relationship history for MSHA mine 4105301

Current hierarchy: **Tracy  Schieffer; Rick  Helmcamp → A.L Helmcamp, Inc. → Mentone GP Crushing Facility**

- 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:** A.L Helmcamp, Inc. → Mentone GP Crushing Facility; 2017-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tracy  Schieffer et al → Mentone GP Crushing Facility; 2017-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Tracy  Schieffer et al → A.L Helmcamp, Inc.; 2017-09-26 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Rick  Helmcamp et al → A.L Helmcamp, Inc.; 2017-09-26 to current/open; source msha-controller-operator-history