On 7 May, a tanker poured ammonia into Arkaitzerreka, together with the Zubieta incinerator, according to the company managing it, Ekondakin, composed of Urbaser, Meridiam, Altuna and Uria, Moyua and LKS. The Waste Consortium of Gipuzkoa (GHK) explained in a statement that it has opened a dossier of sanctions against the company. This has been communicated to the Council of Gipuzkoa, the Basque Government and the Basque Water Agency.

Last weekend several witnesses warned of the presence of dead fish in the river and assured that contamination could come from the incinerator. However, the Environment Deputy of Gipuzkoa, José Ignacio Asensio, denied that the incinerator has "a closed water management system".

The URA agency was responsible for investigating the spillage, which was subjected to a series of samples for this purpose. It is precisely Asensio, along with other PNV and PSE positions, who is the administrator of this public agency and the Anti-Incineration Movement has denounced that this is an organization "controlled from the short rope by the authorities".

The City Council of Usurbil also took samples on its own of the dead fish and confirmed that a very high amount of ammonia has been found in Arkaitzerreka: "In the streams of the area the concentration is usually 1 mg/l of ammonia, but on Sunday 62 mg/l of ammonia were measured," explains Noaua.

We are not mistaken, Mr Asensio: The contamination of Arkaitzerreka has been caused by the incineration plant. And now what? What corrective measures will you take not to repeat? What control mechanisms exist? Who will protect us? We need answers: transparency," said the mayor of Usurbil, Agurtzane Solaberrieta.

According to GHK, in the infrastructures that make up the Gipuzkoa Environmental Centre (incinerator, TMB plant...) the closed circuit has worked "correctly". The landfill has occurred inside the plant, but also outside, with the same negative result.