Concentrations and dynamics of carbon dioxide, radioactivity and radon in two caves of Italian Classical Karst (Municipalities of Sagrado and Savogna d’Isonzo)

A 13-month monitoring was carried out in two caves that open up the north-western sector of Classical Karst (Gorizia Karst): Antro Casali Neri and Grotta Due Piani. In both, ß + γ radioactivity, radon CO2 have a seasonal pattern, with maximums summer minimums winter, even if their trends are somewhat different, due to different morphological thermal conditions. The increases begin when outside temperature becomes higher than vice versa, decrease is recorded below cave temperature. more modest daily variations radon, on other hand, evident its concentration low. Sometimes they related meteorological or day/night rhythms, but, cases, no clearly identifiable causes. maximum activity 50161 Bq/m3, while went off instrument's scale (> 9999 ppm) only first days August 2021. highest radioactivity value also this 0.85 μSv/h (average 8 minutes recording), peaks 1.05 μSv/h. Piani cave, lower, 22138 however, values from July October both warm months, appear come mainly fractured rock epikarstic zone. Further accumulations can then form points poor ventilation. Furthermore, research has shown high concentrations these gases not typical large deep caves, but easily accessible caves.