Wastewater Residuals

Residuals are the organic residues removed from wastewater during the treatment process.

These nutrient-rich, solid, semi-solid, or liquid residuals may be incinerated or landfilled. However, if of sufficient quality, these materials may be applied to farmland as a fertilizer.

Such residuals are often called biosolids. Biosolids may not be the prettiest material, but to crops hungry for nutrients, they can be a beautiful sight.

Since 1993, NEIWPCC’s Residuals Workgroup has improved interstate communication on issues associated with residuals from wastewater treatment, drinking water treatment, and on-site sewage disposal. The workgroup meets 3 or 4 times a year. The group comprises staff from NEIWPCC and the EPA, and the residuals coordinators  from each of our member states’ environmental agencies.

The Residuals Workgroup promotes compatibility among state and federal sludge and septage management programs. NEIWPCC provides a forum for interstate discussion as well as technical assistance and coordination.

A recent addition to NEIWPCC’s residuals-management expertise has focused on fats, oil, and grease (FOG). The environmental community is moving to manage FOG more stringently. There needs to be adequate treatment capacity to manage the material removed from private and municipal wastewater systems.

NEIWPCC’s FOG workshops and associated resources have highlighted treatment alternatives for this material. Treatment options discussed include private grease pretreatment facilities, composting, land application, and incineration (with municipal solid waste and sewage sludge).

The workshops have focused on treating the material once it is removed from the wastewater system. They emphasize that there are properties within this material making it suitable for various types of beneficial reuse.

Meeting Materials: September 26, 2019