When surveying a property in Sarnena Sredna Gora, we were asked to do an electrolyte analysis and measure radon in borehole water. The good news is that we did not encounter any significant deviations in the measurement of radiation, radon, electromagnetic smog, air quality and structural dampness at the property. The not-so-good news is that we came across a region that was drilled for radioactive metals decades ago and where property owners often use their own boreholes for domestic water supply.
In the same area, we have also measured high radon values in buildings and water wells. But this time we were shocked by the result of 500 pCi/l or 18,500 Bq/m3, which in addition to being the highest value our device can measure is also 185 times higher than the accepted safe norm of 100 Bq/m3. We immediately advised our customers to stop using the borehole water, because just after taking a shower in the bathroom, with it the radon levels in the room increased 4-5 times.
We were surprised that the owners received a positive opinion from the Regional Health Inspectorate (RHI) for using the water for domestic purposes. We assume that the RHI does not test the water for of radon, which in our opinion should be mandatory for areas where drilling for radioactive metals has been done, especially since the presence of uranium in the water has been found in neighboring settlements and temporary bans on the use of water from local water sources have been imposed.