Borough solid waste division starts work on wood debris composting project

The Matanuska-Susitna Borough’s solid waste division has two new projects underway, one which will save the borough about $200,000 a year in costs of hauling contaminated rainwater from the borough landfill to Anchorage for treatment, and a second the first phase of an organic compost collection program that has been long in the planning.

The borough assembly gave the go-ahead recently for a $1.4 million phase one of the compost program, which will involve purchasing equipment and upgrading transfer sites for the collection and processing of woody debris, which can then be used in gardening or other agricultural purposes.

A phase two, planned once the balance of the funding is provided, is to upgrade the transfer sites in Big Lake, Willow and Talkeetna with compost collection and improved household hazardous waste disposal, according to Jeff Smith, manager of the borough’s solid waste division.

The assembly had given the borough permission to apply for a $3 million federal grant from the U.S. Environmental Protection Agency’s Solid Waste Infrastructure for Recycling program. EPA awarded $1.44 million of this for the first phase, involving woody debris, leaving the balance of the grant available for the second phase.

Smith said the landfill operators now accept tree waste or woody debris at the Palmer Central Landfill site and grind it to a size suitable for spreading on slopes for stability. Tree waste delivered to the satellite solid waste transfer sites operated by the borough in Big Lake, Willow and Talkeetna is burned, Smith said.

The EPA grant will also pay for upgrades, including for hazardous waste handling, at the Central Landfill and the regional solid waste collection sites.

Equipment purchased with the new EPA grant will allow woody debris to be ground to a finer size in Palmer and for debris to be collected and transported to Palmer for processing from the solid waste transfer sites.

The material will then be trucked back to the transfer site and stockpiled for local residents to use. This will eventually be free but at some point a fee may be changed to cover costs, Smith said.

Equipment is being ordered now for the new compost program which could take 12 to 18 months for delivery. The borough expects the program to be up and running in 2025, Smith said.

Expanding this to food organic waste composting could happen in the future will be more complicated, requiring more engineering and equipment in the second phase. One challenge is that the nitrogen content of the food waste must be managed so that it is not too high, he said.

On the reduction of wastewater now trucked to Anchorage, Smith said the plan is to build an evaporation unit that to reduce the amount of water needing disposal by about 90%. Methane gas now produced at the landfill will fuel the evaporation unit. The methane is now incinerated at the site.

The new evaporation system will cost $4 million to $4.5 million to build to install and the borough will fund this internally from cost savings. The borough now transports about five million gallons of contaminated wastewater yearly to Anchorage’s municipal water treatment plant..

A 90% reduction of the wastewater through evaporation will save about the borough approximately $200,000 a year, Smith said.