Many-year monitoring data on the ~(90)Sr and ~(137)Cs levels in water of the Neva River and Lake Ladoga are presented. In 1970-1990, the ~(90)Sr level in the Neva River steadily increased. In 1991, a radiological survey was made of the Kit experimental vessel with radioactive wastes in its holds, which was on berthing in the northwesteren part of Lake Ladoga. ~(90)Sr, ~(137)Cs, and ~(239,240)Pu were monitored in water and bottom sediments near the Kit vessel berthing after it was towed outside Lake Ladoga. In 2001, the ~(90)Sr concentration in water of Lake Ladoga and the Neva River considerably decreased.
展开▼
