In August 1985 the Environmental Engineering Committee of the Science Advisory Board was asked by the Office of Water Regulations and Standards (OWRS) to review technical documents supporting development of EPA regulations for the disposal/reuse of sewage sludge under Section 405(d) of the Clean Water Act. The Committee was also asked by the Office of Marine and Estuarine Protection (OMEP) to review technical documents supporting revisions of the EPA ocean dumping regulations. The Committee chose to review the two sets of documents together, since they both dealt with a common subject, and since they shared, in some respects, a common methodology. The report, however, covers only the review of the OWRS documents, which consist of a set of risk assessment methodologies (1,2,3,4) for four sludge disposal/reuse options (landfilling, land application/distribution and marketing, incineration, and ocean disposal). The reviews of the OMEP documents are covered in separate Committee reports. The Committee's principal findings are outlined.