"In order to successfully complete the removal of hazardous waste deposited in the heaps of the old mines of São Pedro da Cova, it becomes necessary to resort again to the legal mechanism provided for in the CCP [Public Procurement Code], regarding the execution of complementary services beyond the quantities initially planned and to authorise additional expenditure of two million euros," the text of the resolution states.

Among other reasons invoked, the order justifies the additional expenditure because the progress of the work has made it possible to detect hazardous waste "outside the limit zone defined for intervention, with part of the waste lying along a long slope, which was totally inaccessible at the time of the surveys.

According to the ordinance, there was also "the frequent appearance of several contaminated ferrous masses, with a density about five times greater than the density of the mass of waste".

The removal of this waste in that parish in the municipality of Gondomar, Porto district, began in October 2014, more than 10 years after the deposit, in an initial phase that ended in May of the following year, with the removal of the first 105,600 tonnes.

Over the years, this situation has motivated questions and requests from political parties, as well as local initiatives such as vigils, concentrations and protests, and the sending to the Prime Minister, António Costa, of thousands of postcards with the phrase "Total removal of hazardous waste in São Pedro da Cova now", accompanied by images symbolising danger signs.