Aerobic Garbage Reduction

While the legislature is rumored to be heading toward adjournment sine die by Friday, March 26, some legislation other than budget-related has been introduced, passed committees in both House and Senate and passed on the floors for both chambers. One of the most interesting, dealing with land fills, was introduced on February 25th.

HB 599 allows the Idaho Department of Environmental Quality to review, approve, and issue research, development and demonstration permits for design, construction and operation of bioreactor landfill operations.

There are currently 70 bioreactor landfills in operation in the country. Bioreactor landfills work by breaking down waste and converting it to other useful purposes over the course of years instead of decades, reducing the need to site new landfills as frequently. They also produce electricity by expanded production of methane gas.

The Solid Waste Association of North America (SWANA), characterizes a bioreactor landfill as that in which "liquid and gas conditions are actively managed in order to accelerate or enhance biostabilization of the waste... significantly increasing the extent of organic waste decomposition, conversion rates, and process effectiveness over what would otherwise occur with the landfill.”

In basic terms, it takes the addition of liquid and air to increase decomposition. Regular landfill waste often does not have enough moisture to meet the microbial needs for this process. Bioreactor landfills add liquid and sometimes oxygen to speed up anaerobic waste decomposition by turning it into aerobic decomposition.

Bioreactor landfills convert waste to other useful purposes faster than standard practices—in a matter of years instead of decades. As waste breaks down, it decomposes and is converted into gas which could be used to produce power while decreasing greenhouse gases. The process results in a 15 to 20 percent recovery of landfill space, could provide an alternative to land application of some liquid wastes, and reduces costs for garbage disposal.

The legislation stipulates additional environmental controls for bioreactor landfills and limits such operations to facilities with sufficient design to accommodate bioreactor operations and gas recovery systems.