ENVIRONMENTAL disasters do not recognise state borders, Slovaks realised after the spill of toxic red sludge on October 4 near the town of Ajka in Hungary, about an hour’s drive from the Slovak border. The toxic sludge flowed swiftly across seven Hungarian villages, leaving several people dead, scores injured, and many more homeless; the wide extent of the contamination of soil, water and air may have a long-term detrimental impact on the whole region.
The Environment Ministry in Bratislava reported that the Slovak Water Management Company has been monitoring pollution levels in the Danube River between the mouth of the Moson branch of the Danube and the town of Štúrovo following the sludge spill. The analyses released on October 12 showed pH levels between 7.91 and 8.12, which the water management company said was normal.
According to the report, the pH of the monitored section of the Danube had returned to its normal level on October 9.
The concentration of heavy metals in the waters of the Moson branch of the Danube, mainly aluminium, vanadium and arsenic, fell below the upper permitted levels on the morning of October 9 or sometime before. In the Danube itself, the content of vanadium and aluminium exceeded the limits only on the Hungarian bank of the river. After mixing with the up-river Danube waters the concentration of these metals decreased significantly and measurements of pH in Štúrovo showed the same level as before the spill of red sludge.
Another series of water-quality measurements was planned for October 18.
The Slovak branch of Greenpeace monitored the pH values and concentrations of heavy metals in the Danube on their own. Kateřina Věntusová, the campaign coordinator for Greenpeace who conducted the fieldwork in Hungary, said in an interview with The Slovak Spectator that the pH value in the Raba River and the Moson branch of the Danube reached approximately 9 on October 7, significantly over the normal pH of 6.5. She confirmed that on October 9 the measured pH value had dropped to 7.
“Despite the fact that the pH values have stabilised and neutralised in the Raba and the Moson branch of the Danube, the present status doesn’t mean that the rivers are not contaminated with the red sludge anymore,” Věntusová told The Slovak Spectator, adding that the quality of the water will be influenced by the continuing presence of the heavy metals which are a more significant long-term problem.
“It’s likely that for some time it will not be possible to fish in these sections [of the rivers],” Věntusová said. She added that many dead fish have been found on the banks of the rivers.
The Slovak Association of Fishermen (SRZ) announced on October 11 it was preparing a ban on fishing on the Danube from Štúrovo to Veľký Meder in cooperation with the Environment Ministry in response to the disaster in Hungary.
Věntusová explained that the huge amount of red sludge – about a million cubic metres – that escaped into the environment after the reservoir retaining wall burst contaminated soil, air and water alike. The contamination has spread from the point of the spill into the wider environment via the air and water.
Contaminated dust from the area has spread through the air and has reached distant areas, and contamination via waterways has caused the Danube River in the territory of Slovakia to be spiked with heavy metals as well, Věntusová said.
The red sludge is toxic waste from the production of aluminium oxide. According to analyses carried out by Greenpeace the measured concentration of arsenic in the sludge was double the limit value that such a red sludge should contain. Arsenic is toxic to both plants and animals and it causes damage to the human neural system if it accumulates in the body. Greenpeace said that given the volume of sludge that spread across the landscape, it is quite possible that as many as 50 tonnes of arsenic were released into the environment.
“There has been no such case in the world in which this kind of sludge escaped into the environment,” Věntusová said. This is why it is still difficult to predict what the impact of the contamination will be on the environment on the Slovak side of the Danube.
The site of the spill is less than 100 kilometres from the Slovak border.
Borders do not stop pollution
“Slovakia must definitely be prepared to react and remediate accidents that happen abroad that can endanger the environment and the health of people on the territory of Slovakia,” Věntusová said, adding that in this particular case Greenpeace expects Slovak authorities to keep monitoring the quality of water and air in Slovakia, to inform the public about the results and to subsequently take measures to eliminate any contamination in the Slovak environment.
On October 12 the Slovak parliament requested that the government submit a report within 30 days on the potential impact on Slovakia of the ecological disaster in Hungary and on the measures that have been taken in response, the SITA newswire reported.
“This tragedy at the same time serves as a warning to Slovakia because here in Slovakia we’ve also got sludge reservoirs that could potentially cause a serious ecological calamity,” Věntusová said.
Roman Karlubík, the president of the Association of Chemical and Pharmaceutical Industry in Slovakia, told the SITA newswire that there is no threat of a similar disaster in Slovakia but noted that there are environmental burdens in the country that belong among unresolved environmental issues which represent a certain risk, noting particularly old waste dumps and sludge reservoirs that were built in the 1950s.
18. Oct 2010 at 0:00 | Michaela Terenzani