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This paper focuses on constraining the erosion rate in the area of the Allchar Sb-As-Tl-Au deposit (Macedonia). It contains the largest known reserves of lorandite (TlAsS2), which is essential for the LORanditeEXperiment (LOREX), aimed at determining the long-term solar neutrino flux. Because the erosion history of the Allchar area is crucial for the success of LOREX, we applied terrestrial in situ cosmogenic nuclides including both radioactive (26Al and 36Cl) and stable (3He and 21Ne) nuclides in quartz, dolomite/calcite, sanidine, and diopside. The obtained results suggest that there is accordance in the values obtained by applying 26Al, 36Cl, and 21Ne for around 85% of the entire sample collection, with resulting erosion rates varying from several tens of m/Ma to ∼165 m/Ma. The samples from four locations (L-8 CD, L1b/R, L1c/R, and L-4/ADR) give erosion rates between 300 and 400 m/Ma. Although these localities reveal remarkably higher values, which may be explained by burial events that occurred in part of Allchar, the erosion rate estimates mostly in the range between 50 and 100 m/Ma. This range further enables us to estimate the vertical erosion rate values for the two main ore bodies Crven Dol and Centralni Deo. We also estimate that the lower and upper limits of average paleo-depths for the ore body Centralni Deo from 4.3 Ma to the present are 250-290 and 750-790 m, respectively, whereas the upper limit of paleo-depth for the ore body Crven Dol over the same geological age is 860 m. The estimated paleo-depth values allow estimating the relative contributions of 205Pb derived from pp-neutrino and fast cosmic-ray muons, respectively, which is an important prerequisite for the LOREX experiment.

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Measurements of radon concentration in the underground low-level laboratory in Belgrade, Serbia with a discrete sampling (T=2 h) have been performed. From July 2008 to July 2010, the time-series analysis was carried out. Also, the simultaneous measurements of meteorological parameters (temperature, atmospheric pressure and relative humidity) in the laboratory were done. The simultaneous monitoring of these parameters shows the correlation between temporal variations of radon concentration and meteorological parameters. Also, the radon time-series analysis has been used to study the possible correlation between the anomalous behaviour of the radon concentration and the local seismicity.

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Digital ratemeter that operates according to a self-adjusting algorithm, which at low rates automatically switches from a preset count to the preset time method, is proposed. It combines the good properties of both methods concerning the accuracy of the measured average counting rate and the response time to sudden changes of rate.

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A simulation programme based on the Geant4 toolkit has been developed to simulate the coincident responses of a plastic scintillator and an HPGe detector to the cosmic-ray muons. The detectors are situated in a low-level underground laboratory (25 m.w.e). Primary positions, momentum directions and energies of the muons are sampled from the angular and energy distributions of the cosmic-ray muons at the shallow underground level. Obtained coincident spectra of both detectors are presented and discussed.

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We suggest that radioactive food contamination, as determined solely by a quantitative gamma-ray spectroscopic measurement, may, apart from the total activity per unit mass, be for quick reference conveniently characterized by another single figure which we call the "Gamma Contamination Food Factor" (GCFF). This factor may be defined as the ratio of the total specific activity of gamma-ray-emitting radionuclides in the food sample (except that of 40K) to the specific activity of 40K either in the sample itself or in an "average man". We discuss briefly the meaning and advantages of these definitions.

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