Abstract: The trend of ³H concentration over the years since Daya Bay Nuclear Power Base runs was analyzed for ambient air, drinking water, reservoir water and sea water around the base and groundwaterin the base sector. It turns out that, in the prevailing direction of radioactive gaseous discharge, ³H concertration in ambient air at monitoring pointswas slightly increased with the radioactive gaseous discharge of the base increased. And with the distance from the base increased, a downward trend is exhibited. The ³H concentrations in drinking water and reservoir water around thebase are currently in background levels. For seawater around the base's outfall,³H concentration is slightly higher than the background level. However, no accumulative trend was observed for all monitoring points over the years. Currently the discharge of ³H from the base had no impact on the environment and public.

Key words: PWR, Environment, Tritium, Analysis