The magnetic field at transmission lines is quite high (the greater the greater the power is transmitted, the greatest is at LV lines). However, this field weakens very quickly as you move away from the wire. No one has yet unequivocally stated the harmfulness of the magnetic field with a frequency of 50 Hz, much more harmful are high-frequency fields, even those from a mobile phone (the more that we hold it to the ear while talking). Of course we all use cells and we don't care, but the power line is deadly

. I share the opinion of Col. stomat. You should think carefully about buying this plot and it all depends on whether the line goes through the center or on the edge of the plot, find out in the ZE if they have any plans to modernize this line in the near future, etc. If the price is attractive and the plot itself is nice, maybe it's worth it to buy.
Marcin, I know that there are technologies that you write about, but I do not believe that suddenly all electric power plants will replace overhead lines with cable lines. It is too expensive and you can count on it. Overhead lines are still being built and for a long time they will be built not only in our own but also around the world because they are much cheaper, and it is not old technology but economy. As for the cables, the oldest one I have repaired was from 1928 at 15KV. He works to this day and no one thinks about replacing it. In the area where we work, we still have a few MV cables from the 1930s and they are in much better condition than cables from the 1970s and 1980s, and failures on them are rare and only in places where they were repaired sooner and repaired after the war, because pre-war joints they still work without failures.