San Fernando Sewage Treatment Plant Optimization

Description: This project corresponds to the optimization of the San Fernando Sewage Treatment Plant and aims to expand the capacity of the Treatment Plant, considering the projected demand by 2030, which is estimated at a population served of 71,383 inhabitants . This requires the modification of the project "San Fernando Wastewater Treatment Plant Improvement", qualified environmentally friendly by means of SR No. 57 of March 8, 2006 of the Regional Commission for the Environment of the Libertador Region General Bernardo O'Higgins. It should be noted that two pertinent queries related to the Sewage Treatment Plant (WWTP) of San Fernando were submitted. The first was aimed at correcting discrepancies with the original project and was resolved by means of Letter No. 266 of March 14, 2012. The second query refers to the "Sander Sewage Treatment Plant Sander" project, which considered the incorporation of a sludge liming system for the plant, resolved through SR No. 109 of June 1, 2015. In both cases it was resolved that said changes did not constitute significant changes that merited the obligatory entry of these projects into the System of Evaluation of Environmental Impact. The letter and the indicated resolutions are attached in Annex 2. Currently the Sewage Treatment Plant consists of a preliminary treatment, followed by a secondary treatment of activated sludge, consisting of two aerated reactors and two settlers, with recirculation and sludge purge, and finally a contact chamber for the disinfection of the effluent. . The effluent from the plant is discharged into the Nincunlauta Canal, in compliance with the limits established in Table Nº1 of DS No. 90/2000 MINSEGPRES, emission standard for the regulation of pollutants associated with discharges of liquid waste to bodies of surface water. On the other hand, the sludge generated in the system goes through a process of thickened, aerobic and dehydrated digestion, to finally be whitewashed and transferred to an authorized disposal site. The modifications to the Sewage Treatment Plant submitted to environmental assessment will be developed in two stages. The first stage to start the year 2018, considers the renovation of the storm dump, the habilitation of a new reactor, renewing the aeration system and the associated flow distribution chamber, the incorporation of new recirculation and sludge purge pumps and of a system of mechanical thickened sludge. For its part, the second stage will be carried out in 2021 and involves the incorporation of a new sedimentation plant and the renovation of the associated flow distribution chamber. Objective The objective of the project is to expand the capacity of the Sewage Treatment Plant of San Fernando, considering the projected demand by the year 2030, which is estimated at a population served of 71,383 inhabitants. To do this, it is necessary to modify the "San Fernando Wastewater Treatment Plant Improvement" project, qualified as environmentally friendly by means of SR No. 57 of March 8, 2006. Annex 2 contains the aforementioned resolution.