The reuse and recycling of waste paper sludge is increasing rapidly as far as the economical and positive environmental benefits are realised. In this study, primary sludge coming from a large production plant, located in the centre of Italy, was collected and the environmental quality of the sludge was assessed through geotechnical, physical and chemical analysis and leaching tests, as required by the Italian regulation on solid waste recovery. The results suggest that primary sludge from paper industry do not represent a major threat for the environment in regard to the heavy metal content. The use of this sludge for in situ applications appears an interesting avenue for an integrated management of waste from the paper industry. (C) 2004 Elsevier B.V. All rights reserved.