After the collapse of communism, there existed significant differences between the post-socialist countries' attitudes to the environment, the environmental ideology, and many other things.
Czechoslovakia would switch socialism to capitalism but there were clearly many business-as-usual projects that simply had to continue. That included the expansion of nuclear power plants - which have been attacked by anti-nuclear Austria - and the completion of Gabčíkovo Waterworks that were originally meant to be a common Slovak-Hungarian project, Gabčíkovo-Nagymarosz Waterworks.
The red mud that will be discussed later
However, there was an apparent consensus in Hungary that the end of communism meant that there would never be any new big projects. "Big projects" and "big buildings" were equated with communism. The attitude of Slovaks and Czechs couldn't have been more different. "Big projects" have nothing to do with capitalism or socialism: the two systems just realize them in different ways. So while Slovakia continued to build the dam - to prevent the big floods and other things - Hungary unilaterally breached the 1977 Czechoslovak-Hungarian Budapest Treaty.
Needless to say, the new nuclear plant in Czechia's Temelín is doing its job nicely and safely, much like Slovakia's Gabčíkovo Waterworks. The latter structure has some negative side effects but it also has many positive side effects, including the environmental ones.
Nevertheless, nuclear power plants and big dams are negative symbols for the environmentalist ideologues, much like the wind turbines and solar panels are their positive symbols. All green people are obliged to worship the wind turbines and to criticize dams and nuclear power plants.
However, if something is a negative symbol for a quasi-religious movement, it doesn't mean that it's actually the most dangerous thing for the environment. You should better watch the more obvious, more toxic, striking threats whose negative impact is uncontroversial even outside the environmentalist quasi-religious movement.
Unfortunately, Hungary has provided us with a shocking proof of this assertion on Monday, October 4th:
Ajka alumina plant accident (Wikipedia)In a company not too far from the Slovak and Austrian borders producing aluminum by the Bayer process, one million of cubic meters (that's like a cube whose side is 100 meters) of toxic waste which is a by-product of the technology were waiting behind a wall.
The wall broke on Monday and I don't have to explain you what one million of cubic meters of toxic junk can do, especially if it has lots of titanium and vanadium compounds, besides other heavy metals, and if it instantly sends pH of the landscape around to 12 or so (recall that 7 means pH neutral).
The disaster, which has killed 4 people and injured more than 100 people (other casualties are arguably waiting in the pipeline), has already been classified by Greenpeace as one of the three worst environmental tragedies in Europe in the last 20-30 years. And they may be right about this one.
Today, sadly, it was reported that the junk has reached the Danube. However, the pH and other things is quickly approaching the normal levels and I guess that the life will deal with this stuff somehow.
However, several villages that were affected by the disaster will remain empty - they will be turned into peopleless memorials of this particular incident. People and societies will react much more sensitively than other forms of life - because we the humans enjoy much bigger standards of the environmentalist luxury than other plants and animals. Needless to say, if we didn't care about a slightly increased risk of diseases or death, we could live in those villages, anyway. But we do. And the richer we become, the more we care.