# Relationship history for MSHA mine 1001834

Current hierarchy: **Ernest W Johnson; Robert E  Johnson → Mountain West Products LLC → Siddoway Pit**

- 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:** Hecla Mining Company → Siddoway Pit; 1987-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Gerald  Taylor et al → Siddoway Pit; 1988-02-01 to current/open; source msha-controller-operator-history
- **operator_operates_mine:** Mountain West Bark Products Inc → Siddoway Pit; 1988-07-01 to 1993-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Gerald  Taylor et al → Mountain West Bark Products Inc; 1988-07-01 to 1993-11-30; source msha-controller-operator-history
- **controller_controls_operator:** Frank  Daniels et al → Mountain West Bark Products Inc; 1988-07-01 to 1993-11-30; source msha-controller-operator-history
- **operator_operates_mine:** Mwca Inc → Siddoway Pit; 1993-12-01 to 2000-03-14; source msha-controller-operator-history
- **controller_controls_operator:** Hecla Mining Company → Mwca Inc; 1993-12-01 to 2000-03-14; source msha-controller-operator-history
- **operator_operates_mine:** Mountain West Products LLC → Siddoway Pit; 2000-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robert E  Johnson et al → Siddoway Pit; 2000-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robert E  Johnson et al → Mountain West Products LLC; 2000-03-15 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Ernest W Johnson et al → Mountain West Products LLC; 2000-03-15 to current/open; source msha-controller-operator-history