115 Figure 2 – Type I cover Granular material (0.075 m thick): It had the function of filter and drainage of the waters that could cross the topsoil by means of a catchment system, the waters were derived from the waterproofed wastewater tank. Topsoil or topsoil (0.15 m thick): Its function was to support the native grass species planted for revegetation. Geomembrane: This geosynthetic made of 1.5 mm double textured HDPE (high density polyethylene) was used to encapsulate the reservoir and contain the flow. Based on PNN (net neutralization potential) analyses, this reservoir had a potential to generate acid drainage, making it necessary to reduce the infiltration levels of non-contact water with the acidgenerating material. The geomembrane used follows an international standard specification GM13 of the GSI (Geosynthetics Institute) that guarantees good mechanical performance, due to its high resistance to chemical and biological degradation, as well as its high resistance to ultraviolet rays. Nonwoven geotextile: This material made of PP (polypropylene) with a grammage of 270 g/m2 was placed under and over the geomembrane for puncture protection purposes. The profiled slopes could present puncture zones that could damage the geomembrane during the process of installing the geosynthetics and filling the cover materials. Geocell: The geocell, made of HDPE followed the GSI GS15 standard specification, with dimensions of 100mm in height and 508mmx475mm in opening. The purpose of the geocell was to improve the short- and long-term stability conditions of the cover on the 2H:1V slope. This cover was made of 75mm of granular material for drainage of precipitation infiltration and 150mm of topsoil for vegetative growth with native species. The geocell contributes to generating a macrocorrugation along the slope, the geocell walls increase the stability influence of the cover beyond 100 mm thickness, which made it unnecessary to confine the cover in its
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