An Economic Framework for Evaluating the Benefits and Costs of Biosolids Management Options
Robert S. Raucher Diane Garvey K. C. Hallett Jim Henderson Carolyn Wagner
OverviewAgencies responsible for wastewater treatment have choices regarding how they manage their treatment process residuals. They can consider them waste products requiring suitable disposal (e.g., liquids managed as wastewater effluent, and sludges directed to traditional landfills), or as potential resources with significant "beneficial use" potential. For example, effluent can be rendered into reclaimed water, and solids can be used beneficially as a soil amendment in land applications and mine site reclamation, tapped as a renewable bio-fuel for energy production, or applied in other beneficial manners. Beneficial use options for biosolids management can generate important benefits to the utility and the community it serves. However, in some instances these beneficial use options also may have the potential to impose additional costs and/or risks. These benefits, costs, and potential risks generally accrue not only to the wastewater agency alone, but also to society as a whole (including the environment).
As stewards of the environment and public trust, wastewater agencies need to consider the full range of benefits and costs associated with their activities. This means that they need to take into account all the impacts - good, bad, and uncertain - that their activities may impose on the broader community. Likewise, utilities cannot in good faith focus exclusively on the direct financial impacts on their agency alone. Instead, utilities also need to take account of the "externalities" their activities bestow (or impose) on the broader community: they need to think beyond the fence.
This report describes the approaches, methods, and tools available to help utilities take a broad perspective and develop benefit-cost comparisons of their biosolids management options. This is designed to help agencies understand why it is important to conduct such analyses and why it is important to adopt a broad social accounting perspective when doing so. This report also provides tools and guidance to help utilities conduct such BCAs or related forms of Business Case Evaluation (BCE), including the Triple Bottom Line (TBL) approach.