ABSTRACT
On February 19,1993, EPA published its final rule for regulating the use and disposal of sewage sludge. The RIA accompanying the proposed rule assessed the costs and some of the benefits of four alternative regulatory options. The annual compliance cost of the regulatory option preferred by EPA was estimated to be over $150 million. The revised RIA accompanying the final rule similarly presented an assessment of the costs and portions of the potential benefits of regulatory options. However, the estimated cost of compliance for the preferred option in this case was less than $50 million annually-a difference of well over $100 million per year. Such a dramatic reduction in costs from proposal to promulgation resulted both from an improvement in the quality of data used in the analysis and from a lessening in regulatory stringency. Benefits, while not monetized, were probably underestimated in both the initial and revised RIAs because of a failure to recognize potential cost-savings from expanded reuse opportunities. Additionally, in the rulemaking process, other cost-saving opportunities were disregarded, due to concerns about adverse public reaction. Despite these omissions, the total benefits of the scaled-back rule likely still exceeded total costs. In this case study, Mahesh
INTRODUCTION
Municipal sewage sludge is generated at publicly owned treatment works (POTWs) as a by-product of domestic sewage wastewater treatment. These sludges are a combination of water, solids, and contaminants: dissolved substances, including nutrients, metals, inorganic and organic chemicals, pathogens, pesticides, and household chemical wastes. The exact composition and concentrations of these sludge contaminants depend on several factors, including the types and levels of discharges the POTW receives from industrial sources ("indirect dischargers" who are subject to "pretreatment requirements"), and the level of treatment provided at the POTW. Because of the volume and potential toxicity of municipal sewage sludge, public health and environmental concerns about disposal and potential reuse have developed. In 1987, as a result of such concerns, Section 405 of the Clean Water Act was amended, requiring EPA to regulate the use and disposal of sewage sludge.1
