Radioecological state of the territory and water area in Guba Andreev

Abstract

The radioecological conditions which developed on the territory over the long operating time of the object of the naval fleet in Guba Andreev are described. The results of an analysis of the sources of the real and potential danger and measures to prevent dangerous effects for the environment and the workers at the time remediation work is performed are discussed.The buildings and structures at a temporary disposal site for spent nuclear fuel and radioactive wastes in Guba Andreev (a former technical shore base of the northern fleet) were built at the end of the 1950s -beginning of the 1960s. Since spent fuel was added to the disposal site well before the fuel was shipped out, a large amount of fuel (~100 reactor cores from submarines) and radioactive wastes have accumulated at the site. For more than 40 yr of operation, the buildings and structures were not maintained, so that the states of many storage sites are unsafe [1]. Because the storage sites have become leaky, radioactive substances are flowing into the ground waters on the territory. Melted snow and rain water are gradually expanding the zone of contamination and are carrying radionuclides into the water of Guba Andreev.Determination of the Radioecological State of the Territory and Water Area. Periodic examinations of the buildings, structures, territory, and water area of Guba Andreev were conducted by the radiation safety services of the fleet and by specialists from the Research and Design Institute of Electrical Technology (ground survey) and the Russian Science Center Kurchatov Institute (water area). In 2002-2004, the free financial assistance provided by the Norwegian Radiation Protection Agency made it possible to construct cartograms of the radiation contamination ( Fig. 1) and perform hydrogeological and radiation-geological examinations of a large part of the territory of the disposal site. These measurements differed quantitatively and qualitatively from previous measurements: the number of measurements performed on soil samples was ten times larger than the number performed in preceding years, extensive field investigations made it possible to construct cartograms of the γ-ray field of the territory and water area and to identify the locations of sources of radioactive contamination and determine the radionuclide composition. On the basis of these results, a three-dimensional database containing information on the sources of radioactive contamination of the territory, buildings, and structures was constructed. This database can be used to estimate the real and potential sources of radioecological danger and to plan work on eliminating them.

Radiation situation dynamics at the Andreeva Bay site for temporary storage of spent nuclear fuel and radioactive waste over the period 2002–2016

“…The leak took place close to the bottom of the welded metal shell on the border of the old storage facility (built in 1962) and new storage facility (1972)(1973)(1974). The rate of leakage at its peak reached 30 tons per day (specific activity of water 7 was A ud ∼3.7•10 7 Bq l −1 ). Water leaking from the basins in Building 5 was radioactive because, under operational rules in the 1970s, it was permitted to drain water into those basins that had become radioactively contaminated after contact with spent fuel assemblies (SFAs), including examples of contact with damaged assemblies.…”

“…17 1.3•10 17 6.0•10 14 3.7•10 13 6.5•10 11 a The estimate is given for 137 Cs; the short-lived radionuclides were not taken into account. 7 The original measurements were recorded in mCi/l and have been converted to Bq/l.…”

“…Figure 10 illustrates three options of the location of 37 checkpoints on the Andreeva Bay site. In the first case (figure 10(a)), points were selected randomly from the NIKIET array consisting of 1036 measurement points [7]. In the second case (figure 10(b)), points were located in the areas with zero ADER gradients (i.e.…”

Method for performing rapid radiation surveys of the water areas at shore bases of the naval fleet using submersible gamma spectrometers

“…The examination of the natural media in the shore strip and water area was started in 2003. Aside from the conventional sampling methods, the radioactivity of the water and bottom deposits was measured with a REM-10 high-sensitivity underwater spectrometer with a detector based on a 200 × 200 mm NaI(Tl) crystal, previously used for radiation examination of the sunken submarines Komsomolets, Kursk, and B-159 [3][4][5]. This spectrometer made it possible to measure in 1000 sec the concentration of technogenic radionuclides, specifically, 137 Cs at the 100 Bq/m 3 level in water and 10 Bq/kg in bottom deposits.…”

“…1) in order to continue comprehensive investigation of radiologically dangerous waters and sunken objects. The design took account of the experience gained in surveying the sunken nuclear submarines Komsomolets, Kursk, and B-159 and coastal waters near the shore bases of the fleet in Gremikha and Guba Andreeva [5]. The gamma-spectrometers in the complex have a unified electronic part, making it possible to perform measurements in the autonomous regime (the spectrometers can be positioned as a station performing long-term monitoring of the radiation environment for up to 1 yr) as well as in a real-time regime using a cable along which spectrometric information is immediately transmitted to the operator.…”