The Government of Aragon starts another test for the elimination of the lindane residues, called LIFE SURFING, counting with a 2.1 million euros budget. The cofinancing of the European Union to the Project is 57% and the contribution of the Government of Aragon, 570.836 euros. The duration of the Project is four years, from 2019 to 2022.

The objective of this LIFE is to test in the field a series of techniques to destroy the contamination that may reach the water from the old Bailin landfill. For that, the project is focused in the elimination of dense residues adhered to the rock fractures.

The dense liquid residues were only produced during the period of operation of the lindane factory and they came from the distillation tails of the end of the production phase, as well as from the emptying of the facility in case of breakage. This happened often because part of the facility consisted in glass pipes, due to the need of working with ultraviolet rays. These dense residues were dumped in Sardas and in Bailin landfills. As they were denser than water, they have descended through the rock fractures and can be found, in Bailin, at a depth of 45 meters.

The soil of the old Bailin landfill is composed by a 90 % of siltstone very low fractured, but a 10 % of sandstone, with fractures that reach the 45 meters depth.

The dense residues have been pumped for years. Currently, the pumpable dense residues are considered exhausted. What is currently remaining is the dense residue adhered to the walls of the fractures in an estimated amount of 2 to 3m³. Through these fractures a small amount of water from infiltration is also circulating that, once it gets in contact with the dense residues adhered to the rock, it becomes contaminated. Therefore, destroying these dense residues adhered to the bottom of the rock means to eliminate the source of the contamination.

The partners of the Government of Aragon in the LIFE SURFING are the Complutense University of Madrid, through their school of chemical engineering, for the development of previous tests and the design of the pilot test; the University of Stuttgart, for the development of a big scale laboratory test; the IHPA association, that is in charge of the study of the transferability to other locations and SARGA, for the implementation of the pilot test and field works.

From 2014 to 2017, the EU already financed another LIFE called DISCOVERED. This test demonstrated that the oxidation of contaminants dissolved in the water contained in fractures at 40 m depth was feasible. Additionally, the limitation to generate contact conditions in fractures of few millimeters at 45 depth was quantified. As a result of the information provided by this first LIFE, in the lindane challenge and in previous laboratory analysis, an estimate of 60 days is considered necessary to destroy (oxidize) the dense residues, working on field to apply a sequence of technologies.

Therefore, at the new LIFE SURFING, it is needed to implement several technologies in a consecutive way. These technologies are already known individually. This new LIFE test has the challenge of linking them and working on dense residues.

Test Phases

During the development of the works, in 2019, a test to analyze different reactive and surfactants is foreseen, in order to complete the design of the test. In 2020, field works will start. In 2021, the field tests will be finished and tests on cells of several cubic meters will be performed, in laboratory, to analyze the transfer to other ground conditions. In 2020, the elaboration of results and guidelines to implement these works at a full-scale.

The test will be developed over 120 lineal meters of a vertical sandstone layer. The total area to remediate has around 600 lineal meters of the vertical sandstone layer of Bailin site. At the end of this test, if results are positives, the conditions to apply this technology to the rest of the vertical sandstone layer will be determined.

In conclusion, this contribution of the EU, via LIFE funds, will allow for an increase of the safety conditions of the old Bailin landfill and of the use of the water of the river Gallego. The LIFE funds come from the European Union and their objective is the development of field tests of new technologies that have not been proven in the field before, or under such conditions. It has a demonstrative character and, one of the key values of the selected projects is the possibility of transferring the results to other locations with similar environmental challenges. Collaboration among partners from different countries is therefore essential for this project. The LIFE SURFING proposal has been one of the ones selected out of 507 proposals submitted withing the environmental area.

Source: RETEMA