# Relationship history for MSHA mine 3102151

Current hierarchy: **Robbin L  Jones → Wallburg Mulch Sand & Gravel Inc. → Wallburg Sand- US Hwy 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: 2026-10-17T05:35:58.500035+00:00

## Valid-time edges

- **operator_operates_mine:** C & C Mortar Sand Company → Wallburg Sand- US Hwy 1; 2000-06-01 to 2006-10-30; source msha-controller-operator-history
- **controller_controls_mine:** J C  Calicutt Jr → Wallburg Sand- US Hwy 1; 2000-06-01 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** J C  Calicutt Jr → C & C Mortar Sand Company; 2000-06-01 to 2006-10-30; source msha-controller-operator-history
- **operator_operates_mine:** Wallburg Mulch Sand & Gravel Inc. → Wallburg Sand- US Hwy 1; 2006-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_mine:** Robbin L  Jones et al → Wallburg Sand- US Hwy 1; 2006-10-31 to current/open; source msha-controller-operator-history
- **controller_controls_operator:** Robbin L  Jones et al → Wallburg Mulch Sand & Gravel Inc.; 2006-10-31 to current/open; source msha-controller-operator-history