Using Naturally Occurring Radionuclides To Determine Drinking Water Age in a Community Water System

作者：Waples James T^*; Bordewyk Jason K; Knesting Kristina M; Orlandini Kent A

来源：Environmental Science & Technology, 2015, 49(16): 9850-9857.

DOI：10.1021/acs.est.5b03227

Drinking water quality in a community water system is closely linked to the age of water from initial treatment to time of delivery. However, water age is difficult to measure with conventional chemical tracers; particularly in stagnant water, where the relationship between disinfectant decay, microbial growth, and water age is poorly understood. Using radionuclides that were naturally present in source water, we found that measured activity ratios of Y-90/Sr-90 and Th-234/U-238 in discrete drinking water samples of known age accurately estimated water age up to 9 days old (sigma(est): +/- 3.8 h, P < 0.0001, r(2) = 0.998, n = 11) and 25 days old (sigma(est): +/- 13.3 h, P < 0.0001, r(2) = 0.996, n = 12), respectively. Moreover, 90Y-derived water ages in a community water system (6.8 x 10(4) m(3) d(-1) capacity) were generally consistent with water ages derived from an extended period simulation model. Radionuclides differ from conventional chemical tracers in that they are ubiquitous in distribution mains and connected premise plumbing. The ability to measure both water age and an analyte (e.g., chemical or microbe) in any water sample at any time allows for new insight into factors that control drinking water quality.

• 出版日期2015-8-18