In this paper is described a method of simultaneous determination of the total alpha and total beta radioactive level in bodies of water. This method uses low background measuring apparatus with an anticoincidence shield and an Au-Si surface barrie detector. The samples are prepared using the vaporization method for one litre environmental water. The measurement sensitivity is 4.8×10

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Bq/1 for total alpha and 1.9×10

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Bq/1 for total beta. The lowest detection limit is 2.4×10

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Bq/1 for total alpha and 1.9×10

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Bq/1 for total beta.