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The study was carried out in a shallow phreatic aquifer in the piedmont zone between the Atlas Mountains and Tadla plain in Morocco. This study is carried out using physicochemical analyses with statistical analysis (CA and PCA) to show variability of groundwater hydrochemical parameters beneath Beni Mellal city in order to know spatial variability of water quality under urban activities. Total dissolved solid shows large variation from 355 mg/L to 918 mg/L with high values recorded, as electric conductivity, in the city center. High sulfate content is intercepted also in the old city center with values exceeding the threshold in the Moroccan guideline. Sulfate ions are often suspected of having an anthropogenic origin. All water samples show a dominance of Ca against Mg (Ca/Mg: 1.08–6.25) and HCO3 against SO4 (HCO3/SO4: 0.29–6.92). For most of the trace elements, the measured concentrations were far below the standard values except Al and Fe in some samples which exceed all guideline values. PCA of all dataset highlights eight factors with eigenvalues higher than 1 that explained about 80.34% of the total variance. The first two components PC1 and PC2 explained about 41.14% of the total cumulative variance and were responsible for 24.25% and 16.89% of the variance for each one, respectively. The component PC1 is mostly correlated with electric conductivity, TDS, and chloride. The component PC2 was highly correlated with Ca, Cr, and Zn. The dendrogram at a linkage distance of about 10.5 leads to dividing the diagram into three clusters of water samples, C1, C2, and C3. Cluster C1 shows a medium content of EC, HCO3, and NO3 and low content of TDS, Ca, Mg, Na, K, SO4, and Ba compared with C2 and C3. C1 samples show the lowest ion content, resulting probably from the minimal time of residence within the aquifer with low rock interactions. Cluster C2 regroups samples with high content of Ca, Mg, K, SO4, Al, and Cr, medium content of TDS and Na, and low content of EC, HCO3, NO3, and Cl. Samples in cluster C3 have more content of heavy metal (Cd, Fe, Mn, and Ni), CE, TDS, Ca, Mg, Na, HCO3, NO3, and Cl, with low content of Cr and Al and medium values of K and SO4. We recommended the monitoring and follow-up of the water quality under the city and the repair of pipes especially in the downtown area to limit unwanted infiltration. Spatial autocorrelation used with variograms and Moran'I leads to conclude that groundwater parameters varied differently according to the direction, which means that the semivariance depended on direction and distance between samples.

To promote the utilization of sewage sludge as alternative building materials, a study was carried out to examine the characteristics of sewage sludge from wastewater treatment plant of khenifra city, Morocco. Experiments were performed for determining the mineralogical composition, chemical properties, loss of weight, the rate of the calcium carbonate and moisture. Furthermore, the geotechnical parameters deal with the Atterberg limits, water content and Sand equivalent of the sewage sludge material. The purpose of this paper is to present the available information on the various components of sewage sludge to explore the possibility of exploiting this waste in building materials Results show that sewage sludge has neutral pH value around 6.93 and contains organic matter. Moreover, the sludge is composed of a significant amount of oxides and metals. The value of net calorific value (NCV) is 1888.91 Kcal kg -1 . As well as, the mineralogical composition of sludge has been determined by X-rays diffraction (XRD) show the presence of quartz (SiO2), hematite (Fe2O3), aluminum oxide (Al2O3) and calcite (CaO3).The result of the geotechnical properties of sewage sludge obtained indicates a very high value for a liquid limit of 126%, a plastic limit of 100% and the plasticity index of 25% and 128% water content. Based on the data obtained from the characteristics of sewage sludge produced by wastewater treatment plant in the Khenifra city, the utilization of sewage sludge into building materials such as in brick making, ceramics making and in the manufacture of cement are possible, because sludge composition is similar to the raw to construction materials.