[1] J. Yang, W. Liu, L. Zhang and B. Xiao, “Preparation of Load-Bearing Building Materials from Autoclaved Phos- phogypsum,” Construction and Building Materials, Vol. 23, 2009, pp. 687-693. doi:10.1016/j.conbuildmat.2008.02.011
[2] A. B. Parreira, A. R. K. Jr. Kobayashi and O. B. Silvestre, “Influence of Portland Cement Type on Unconfined Compressive Strength and Linear Expansion of Cement- Stabilized Phosphogypsum,” Journal of Environmental Engineering, Vol. 129, 2003, pp. 956-960. doi:10.1061/(ASCE)0733-9372(2003)129:10(956)
[3] H. Tayibi, M. Choura, F. A. López, F. J. Alguacil and A. López-Delgado, “Environmental Impact and Management of Phosphogypsum (Review),” Journal of Environmental Management, Vol. 90, 2009, pp. 2377-2386. doi:10.1016/j.jenvman.2009.03.007
[4] J. P. Bolivar, R. Garcia-Tenorio and F. Vaca, “Radio- ecological Study of an Estuarine System Located in the South of Spain,” Water Research, Vol. 34, 2000, pp. 2941-2950. doi:10.1016/S0043-1354(99)00370-X
[5] P. M. Rutherford, M. J. Dudas and R. A. Samek, “Environmental Impacts of Phosphogypsum,” Science of the Total Environment, Vol. 149, No. 1-2, 1994, pp. 1-38. doi:10.1016/0048-9697(94)90002-7
[6] United States Environmental Protection Agency (USEPA), “National Emission Standards for Hazardous Air Pollutants,” Subpart R, 2002.
[7] “Federal Register,” 40 CFR Part 61, Subpart 61, Vol. 64, No. 2, 3 February 1999, pp. 5573-5580.
[8] USEPA, “Code of Federal Regulations,” Title 40, Vol. 7, Parts 61.202 and 61.204 (40CFR61.202 and 40CFR 61.204), 1998.
[9] J. L. Mas, E. G. San Miguel, J. P. Bolívar, F. Vaca and J. P. Pérez-Moreno, “An Assay on the Effect of Preliminary Restoration Tasks Applied to a Large TENORM Wastes Disposal in the South-West of Spain,” Science of the Total Environment, Vol. 364, 2006, pp. 55-66. doi:10.1016/j.scitotenv.2005.11.006
[10] R. Brina and A. G. Miller, “Direct Detection of Trace Levels of Uranium by LáSER-Induced Kinetic Phos- phorimetry,” Analytical Chemistry, Vol. 64, 1992, pp. 1413-1418. doi:10.1021/ac00037a020
[11] “Uranium Radiation Properties,” WISE Uranium Project, 2006. http://www.wise-uranium.org/rup.html.
[12] H. Tayibi, C. Gascó, N. Navarro, A. López-Delgado, M. Choura, F. J. Alguacil and F. A. López, 5 ème Edition, Journées Internationales des Géosciences de l’Environ- nement, Fès (Morocco), 2009.
[13] W. W. Flynn, “The Determination of Low Level of Polonium-210 in Environmental Materials,” Analytica Chimica Acta, Vol. 43, 1968, pp. 221-227. doi:10.1016/S0003-2670(00)89210-7
[14] H. Tayibi, C. Pérez, F. A., López, M. Choura and A. López-Delgado, “International Congress of Solid Waste Management & Sustainable Development,” Hammamet, Tunisia, 2008.
[15] B. R. Milo? and V. T. Dragan, “Phosphogypsum Surface Characterisation Using Scanning Electron Microscopy,” Acta Periodica Technologica, Vol. 34, 2003, pp. 61-70.
[16] W. C. Burnett, M. K. Schultz and D. H. Carter, “Radionuclide Flow during the Conversion of Phosphogypsum to Ammonium Sulphate,” Journal of Environmental Radioactivity, Vol. 32, No. 1-2, 1996, pp. 33-51. doi:10.1016/0265-931X(95)00078-O
[17] E. M. El-Afifi, M. A. Hilal, M. F. Attallah and S. A. El- Reefy, “Characterization of Phosphogypse Wastes Associated Wit Phosphoric Acid and Fertilizers Production,” Journal of Environmental Radioactivity, Vol. 100, 2009, pp. 407-412. doi:10.1016/j.jenvrad.2009.01.005
[18] “UNSCEAR: United Nations Scientific Committee on the Effect of Atomic, Radiation: Sources and Effects of Ionizing Radiation,” United Nations, New York, 1993.
[19] C. Due?as, E. Liger, S. Ca?ete, M. Pérez and J. P. Bolívar, “Exhalation of 222Rn from Phosphogypsum Piles Located at the Southwest of Spain,” Journal of Environmental Radioactivity, Vol. 95, 2007, pp. 63-74. doi:10.1016/j.jenvrad.2007.01.012
[20] J. P. Bolívar, J. E. Martín, R. García-Tenorio, J. P. Pérez- Moreno and J. L. Mas, “Behaviour and Fluxes of Natural Radionuclides in the Production Process of a Phosphoric Acid Plant,” Applied Radiation and Isotopes, Vol. 67, 2009, pp. 345-356. doi:10.1016/j.apradiso.2008.10.012
[21] EC, “Radiological Protection Principals Concerning the Natural Radioactivity of Building Materials,” Radiation Protection Report RP-112, EC, European Commission, Luxembourg, 1999.