This study investigates the critical issue of salinity intrusion within the Muravera coastal plain aquifer, located in Sardinia (SW), Italy, through a comprehensive hydrogeological investigation. An integrated approach, combining groundwater dating techniques, multi-isotope analysis (including ³H, He, CFCs, SF6, noble gases, Sr, and B), and traditional hydrogeological monitoring, was employed to delineate distinct recharge sources and groundwater flow paths. To mitigate errors associated with seawater mixing, age tracer and noble gas concentrations were calculated specifically for the freshwater fraction, utilizing estimated concentrations for the saltwater component of each sample. Freshwater component concentrations were derived through saltwater component estimations, and subsequent analysis using PANGA and TracerLPM software, assuming a bimodal mixing model, yielded noble gas-derived recharge parameters and mean freshwater ages, respectively. The combined tracer results revealed that several samples were influenced by a geogenic source of SF6 (potentially fluorite mineralization) and possible CFC contamination introduced during sampling. Furthermore, reliable ³H/³He ages could not be determined due to elevated terrigenic helium concentrations and/or apparent loss of tritiogenic ³He for undetermined reasons. Despite these challenges, the age tracers still provided valuable insights. The study identified four distinct recharge sources, including the previously uncharacterized Flumini Uri River, which was found to be a significant contributor. Analysis of the premodern seawater component revealed a high terrigenic helium-4 concentration, exceeding 4 x 10⁻⁷ ccSTP/g, consistent with groundwater ages exceeding 1000 years, indicating extensive mixing with modern freshwater. These findings offer crucial information for developing sustainable water resource management strategies within this vulnerable coastal aquifer.