A yellow-green, foul-smelling liquid is continuing to seep into the Danube at Óbuda every time water levels fall to unusually low levels — yet nothing is being done. So what is happening at the Óbuda Gas Works? During more than 70 years of operation, between 1913 and 1984, around 200,000 tonnes of hazardous, carcinogenic material were buried in the soil of the former Óbuda Gas Works. As that contamination leaches into the groundwater, it continues to pollute the Óbuda stretch of the Danube whenever water levels are low. The question now is no longer whether the problem exists, but when the toxic material will finally start to be removed from the Óbuda Gas Works site.