At Valorsul, what you no longer value and have therefore thrown away becomes a resource again, a raw material that can be transformed into a new cardboard box, a new glass bottle, electricity, fertiliser for agriculture or materials for building a new road.
HOMEPAGE
SUSTAINABILITY
MONITORING
LANDFILL MONITORING
Landfill Monitoring

In accordance with Article 40 of Decree-Law 183/2009 of 10 August, during the operating phase of the landfill, the monitoring and control programme set out in the permit for the landfill waste disposal operation must be carried out. This programme takes into account the requirements set out in part A of annex III of the aforementioned decree-law, such as settlements and filling, the leachate produced, groundwater, surface water and the gases generated.

The pre-treated effluent discharged into the municipal collector from the Leachate Treatment Plant is also monitored, as are the gaseous effluents from the biogas energy recovery system.

Settlement and filling is controlled with the support of an annual aerophotogrammetric survey and topographic control of the land, enabling the identification of filling needs and the modelling of slopes and the surface of areas that are not in operation, as well as correcting the slopes of drainage lines.

Control of the leachate produced and the pre-treated effluent discharged into the municipal sewer involves monitoring its quantity and quality. As far as quality is concerned, the sampling frequency corresponds to that defined in the environmental permit, which is monthly, quarterly and biannually depending on the parameters analysed.

Groundwater quality monitoring in the area where the two landfills are located is carried out on the piezometric network within the landfill area, consisting of 8 piezometers at ASMC and 3 piezometers and 1 borehole at ASO. The sampling periodicity complies with that defined in the environmental permit, being monthly, biannually and annually depending on the parameters analysed.

At the ASMC, surface water is monitored in the Crós-Cós stream, the nearest watercourse, with its source upstream (top west) of the valley where the ASMC is located, flowing into the River Tagus. Sampling is carried out quarterly for the parameters defined in the environmental licence. The ASO also monitors groundwater in the area surrounding the landfill in 2 boreholes and 2 private wells.

The quality of the gases produced is monitored in all the drainage wells installed in the MSW landfill areas. Monthly measurements are taken of the levels of CH4 (methane), CO2 (carbon dioxide), O2 (oxygen) and H2S (hydrogen sulphide). In the biogas energy recovery unit, continuous flow measurements are taken and the quality of the biogas is characterised. The gaseous effluents from the motor-generators are also characterised.