Actinides AMS at CIRCE and 236U and Pu measurements of structural and environmental samples from in and around a mothballed nuclear power plant

Uranium comparison by means of AMS and ICP-MS and Pu and137Cs results around an Italian Nuclear Power Plant

“…The sampling program has been described in [8]. Briefly, the area surrounding the GNPP has been divided into circular crowns each of 1 km radius, from an internal radius of 500 m from the NPP out to 4.5 km (Figure 1).…”

“…The Center for Isotopic Research on Cultural and Environmental heritage (CIRCE), recently upgrated for actinides measurements [4][5][6], and the ANU [7] in collaboration with SoGIN (the Nuclear Plant Management Company) started a research program to measure the concentration and isotopic ratios of U and Pu isotopes in and around the Garigliano Nuclear Power Plant (GNPP) [8]. The measurements employed AMS, and were applied to the analysis of both soil (environmental) and concrete (structural) samples to quantify and determine the origin of any 236 U or 239,240 Pu.…”

“…The measurements employed AMS, and were applied to the analysis of both soil (environmental) and concrete (structural) samples to quantify and determine the origin of any 236 U or 239,240 Pu. In this paper we present results on soil samples, collected up to 4.5 km from the plant and a comparison between the uranium concentration as determined by using ICP-MS by Ecowise and by means of the AMS technique at the ANU (the AMS detailed measurement results for 236 U and 239,240 Pu isotopes for some of the samples are reported in [8]). Evidence of fallout from the Chernobyl accident is present in our 137 Cs gamma activity measurements [8,9].…”

Background reduction in 236U/238U measurements

“…Presently, at the AMS facility of the CIRCE laboratory, isotopic ratios down to 10 À10 are measured using a gas E À DE detector [1][2][3]. This limit is adequate for the measurement of anthropogenic U in environmental and structural samples and allows many applications in the areas of nuclear safeguards and environmental studies [4][5][6][7].…”

Study of236U/238U ratio at CIRCE using a 16-strip silicon detector with a TOF system

“…2 Experimental methods 2.1 CIRCE accelerator and uranium procedure CIRCE, described elsewhere [6][7][8], is a dedicated AMS facility based on a 3MV-tandem accelerator. Briefly the caesium sputter ion source is a 40-sample MC-SNICS and a total injection energy of 50 keV for 238 [4] with a stripping yield of 3.1%.…”