Annen Bros CASE STUDY

Annen Brothers, a third-generation hop farm in Yakima Valley, historically grew and harvested full-vine hops. After securing a USDA NRCS conservation grant, the operation sought to eliminate open-pile disposal of hop vines and instead compost them—along with local dairy manure—to create a high-quality soil amendment. As the hop market shifted, the family decided to retire crop production altogether and convert the facility into a stand-alone commercial composting enterprise. They therefore needed a system that could:

1. Handle a mixed feedstock of hop vines, dairy manure, and—eventually—other commercial green wastes.
   
   
2. Meet NRCS grant performance criteria for aeration control, odor management, and nutrient conservation.
   
   
3. Fit within the farm’s existing footprint without extensive earthwork or above-grade structures that might trigger additional permitting.
   
   
4. Provide real-time process data to satisfy regulatory reporting and guide day-to-day operations as the business scaled up.

Green Mountain Technologies designed and delivered a below-grade Aerated Static Pile (ASP) Sparger system configured as six independent aeration zones—functionally a large, three-bin layout sized for incremental expansion. Key elements included:

• Below-grade sparger system, keeping the working surface unobstructed for loaders while reducing visual impact and permitting complexity.
  
  
• Six individually controlled zones to accommodate variable recipes (hop vines : manure ratios) and staggered batch starts, ensuring each zone receives airflow matched to its biological demand.
  
  
• Wired temperature probes (dual depth) in every zone, providing high-resolution data for turn frequency, moisture adjustment, and compliance documentation.
  
  
• WebMACS™ control platform for remote monitoring, data logging, and automated blower modulation based on temperature set-points—meeting NRCS grant requirements for process verification and enabling future integration of oxygen sensors.
  

Together, these components give Annen Brothers a robust, grant-compliant composting system that converts former crop residues and dairy manure into a marketable soil product while positioning the farm for its new role as a regional commercial composter.