Location(s):

Unity, Maine

Summary:

Since 1990, this site has used the in-vessel Gicom tunnel technology to compost municipal wastewater biosolids and wood waste (sawdust from mill shavings). It is also licensed to accept food discards, wood ash, leaf and yard trimmings, shredded paper, short paper fiber, and fish waste. It has a capacity to accept 145,000 cubic yards of incoming material per year and produces approximately 80,000 cubic yards of finished product, distributed under the earthlife™ brand name to a variety of bulk use outlets. The 4-acre composting operation includes covered storage, mixing and composting buildings, 6 tunnels with a computer controlled air recirculation system, and an ammonia scrubber and biofilter. In addition, 8.5 acres are used for residuals, compost storage, product blending, and windrow curing. The operation also includes facilities for contract research composting and has conducted trials on municipal solid waste, restaurant wastes, paper mill sludge, and various grades of waste paper. The site accepts about 10 tons a month of food discards (including compostable biobased food service ware) from Colby College’s dining halls. The material is composted with biosolids. While this program is largely successful, some plate-sized products were found in the compost curing piles. A couple of compost customers complained. One conclusion is the need for upfront shredding to downsize products in order to facilitate breakdown in the compost piles.

Collection System: 

Uses the in-vessel Gicom tunnel technology

Size of Operation: 

This facility has a capacity to accept 145,000 cubic yards of incoming material per year.

It produces approximately 80,000 cubic yards of finished product, distributed under the earthlife™ brand name to a variety of bulk use outlets.

The 4-acre composting operation includes covered storage, mixing and composting buildings, 6 tunnels with a computer controlled air recirculation system, and an ammonia scrubber and biofilter. In addition, 8.5 acres are used for residuals, compost storage, product blending, and windrow curing. The operation also includes facilities for contract research composting and has conducted trials on municipal solid waste, restaurant wastes, paper mill sludge, and various grades of waste paper.

Challenges: 

Having all materials break down at the same rate

Tips for Replication: 

Could have upfront shredding to downsize products in order to facilitate breakdown in the compost piles