Investigation on radioactive level of gross α and gross β in drinking-water in Huizhou around Daya Bay Nuclear Power Base

Objective: To master radioactive pollution level of drinking-water in Huizhou caused by operation of Daya Bay Nuclear Power Base within a radius of 30 km of the base. Methods: Radioactive levels of gross α, gross β and ⁴⁰K β for source water, processed water and terminal water from seven main tap water supplies were determined to decide whether radioactive pollution on drinking-water is caused by Daya Bay Nuclear Power Base and whether radioactive indexes of drinking-water are in accordance with requirements of water quality, compared to radioactive level of background investigation and screening. Results: In high flow period, radioactive levels of gross α, gross β and ⁴⁰K β for source water were (0.009 ± 0.003 ∼ 0.255 ± 0.029), (0.025 ± 0.003 ∼ 0.211 ± 0.009) and (0.021 ∼ 0.111) Bq/L, respectively; radioactive levels of gross α, gross β and ⁴⁰K β for processed water were (0.011 ± 0.004 ∼ 0.021 ± 0.003), (0.039 ± 0.003 ∼ 0.143 ± 0.007) and (0.025 ∼ 0.108) Bq/L, respectively;radioactive levels of gross α, gross β and ⁴⁰K β for terminal water were (0.007 ± 0.003 ∼ 0.027 ± 0.003), (0.054 ± 0.002 ∼ 0.123 ± 0.006) and (0.037 ∼ 0.109) Bq/L, respectively. In low flow period, radioactive levels of gross α, gross β and ⁴⁰K β for source water were (0.011 ± 0.003 ∼ 0.100 ± 0.008), (0.050 ± 0.003 ∼ 0.139 ± 0.004) and (0.022 ∼ 0.069) Bq/L, respectively; radioactive levels of gross α, gross β and ⁴⁰K β for processed water were (0.005 ± 0.002 ∼ 0.118 ± 0.009), (0.045 ± 0.003 ∼ 0.119 ± 0.004) and (0.022 ∼ 0.065) Bq/L, respectively; radioactive levels of gross α, gross β and ⁴⁰K β for terminal water were (0.010 ± 0.003 ∼ 0.090 ± 0.009), (0.043 ± 0.002 ∼ 0.112 ± 0.005) and (0.024 ∼ 0.068) Bq/L, respectively. Conclusion: During its operation, the base does not cause obviously radioactive pollution to the drinking-water in Huizhou within a radius of 30 km of the base, and radioactive level of the drinking-water meets the requirements of drinking-water quality. (authors)