Annually, approximately 3.6 million dry tons of wastewater biosolids (or sludge) is applied to farmlands, forests, reclamation sites, parks, golf courses and lawns.  This land application is regulated principally by the Clean Water Act, Part 503.  The USEPA is required to periodically review the scientific basis of Part 503 and address public health concerns.

Over two years ago the USEPA commissioned the National Research Council (NRC) to do an independent evaluation of the technical methods of biosolid application.  The intent of this study was to establish standards, focusing on human health protection.  

Findings

The April 2002 NRC report confirmed that there “is no scientific evidence that Part 503 has failed to protect the public health.”  However, the NRC recommended various approaches, surveys and methods to validate the effectiveness of biosolids application methods and monitoring.  

The USEPA is now completing its response to the NRC recommendations.

Reaction

Meanwhile, public pressure grows as anecdotal allegations increase about the health risks of land application.  Consequently, municipalities need to closely monitor the regulatory aspects of biosolids application.  They also need to initiate, (or continue) aggressive programs to ensure that the public has sufficient and accurate information on application practices and risks.

An Assistance Tool

There are tools available to assist municipalities with implementing and monitoring land application programs.  BIO-ARC^® (Biosolids Agronomic Rate Calculator), for example, is a computer-based spreadsheet package designed to make biosolids and application program management easier and more efficient.

Developed by Gannett Fleming, BIO-ARC^® is a series of customized, linked worksheets which compute biosolids agronomic and cumulative pollutant loading rates (CPLRs).

This software was recently updated to account for the latest regulations and to be applicable until 2010.