Biosolids Land Application

The City of Terre Haute Wastewater Utility has a permit (see attachment) that enables its waste byproduct to be used for the enhancement of local farm fields.

Biosolids, or residuals, are primarily organic, solid material produced by wastewater treatment processes that can be beneficially recycled.  This solid material has been processed to a point where it is stabilized. Terre Haute Wastewater Utility produces Class B sludge which can be applied to, and is beneficial for, local farm fields. There are only two ways that the City can legally dispose of these solids:  Through application to farm fields or disposing of it in the local landfill.

Both dry and wet solids are produced. The dry has been run through a belt press and most of the water has been removed to form a cake of solids. The solids are then dumped into a truck and taken to the storage pad. A minimum of 90 days storage capacity is required for the solids. This allows sufficient space so that field application occurs only twice a year, typically in the spring and fall.  There are four lagoons for the storage of wet solids after digestion.  As room is needed in the digesters for the treatment process, these wet solids are pumped from the digesters to these lagoons.

Wastewater has a contract with an independent company that applies both dry and wet solids to permitted farm fields. This process allows beneficial material to be used by local farmers, while minimizing the amount of waste sent to the landfill.  The City saves a considerable amount of money in disposal, application and maintenance costs with this process.  This “green initiative” is good for both local farmers and rate payers.