# Relationship history for MSHA mine 0301944

Current hierarchy: **James J  Johnston → Quality Rock, Inc. → Portable Plant #1**

- 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:** Scott H  Kaufman  et al → Portable Plant #1; 2004-01-19 to 2005-09-27; source msha-controller-operator-history
- **controller_controls_mine:** James J  Johnston et al → Portable Plant #1; 2004-03-10 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Tim  Graham et al → Portable Plant #1; 2005-09-28 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Northwest Arkansas Quarries, LLC → Portable Plant #1; 2007-02-02 to 2013-07-07; source msha-controller-operator-history
- **controller_controls_operator:** Tim  Graham et al → Northwest Arkansas Quarries, LLC; 2007-02-02 to 2013-07-07; source msha-controller-operator-history
- **controller_controls_operator:** Johnelle  Hunt et al → Northwest Arkansas Quarries, LLC; 2007-02-02 to 2013-07-07; source msha-controller-operator-history
- **controller_controls_operator:** Scott H  Kaufman  et al → Northwest Arkansas Quarries, LLC; 2007-02-02 to 2005-09-27; source msha-controller-operator-history
- **operator_operates_mine:** Quality Rock, Inc. → Portable Plant #1; 2013-07-08 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** James J  Johnston et al → Quality Rock, Inc.; 2013-07-08 to current/open; source msha-controller-operator-history