Can we rehabilitate a phosphogypsum stack to a new use that is environmentally safe,financially robust and which adds an economic and social value to the local area? This was the main goal of the project on remediation of a phosphogypsum disposal area of 260 ha initiated in 200 in the city of Sfax which is the 2nd economical pole of Tunisia.Providing a better quality of live for the citizen of the city with the rehabilitation and the reclaim of 6 km of beaches and creating a new urban zone.For this and before clean up actions,the doses received either by people living near the residue deposit with an activity concentration of Ra226 0f 0.4 Bq/g or by workers in case of site remediation were considered to be below ImSv/y.On shore and of shore works were conducted with the depollution of the sea,the removal of the phosphogypsum plaque surrounding the stack,the backfilling with new soil and sand and the confinement of the stack.Simultaneously,a radiological monitoring programme was carried out before,during and after the site remediation.External exposure to gamma radiation and internal exposure due to the inhalation of dusts and radon gas were assessed to evaluate occupational and public exposure.A comprehensive program for site and environmental sampling analysis was conducted to estimate the internal exposure due to the ingestion.The evaluation of the radiation survey resulted in a level of public and workers exposures of less than I mSv/y.Communication with the public and the stakeholders groups has been addressed at all stages of the project by the regulatory authority (CNRP) and the operator (SEACNVS).Similarly,the local population has been involved to participate in a campaign of measurements of radon in 60 dwelling surrounding the site during remediation works.The annual concentration was 32 Bq.m-3 which was comparable to the national average value.The success of the first part of the project is due to the engagement of the government,the operator,the stakeholders and the public opinion.Now,we are face to the biggest challenge to ensure a sustainable and safe development for an attractive urban zone which will offer an important socio-economical impact for the city of Sfax.