3e Water 321 Sr?° in Tap Water - New York City New York City tap water has been analyzed since August 195i. Until the end of November 1956, the sampling period lasted about two weeks during which time an average of 50 liters was collected (3-4 liters per day). Since December 1956, the collections are made over a period of a month and the total volume is about 100 liters. ‘The atrontium 90 content in ppo/liter is shown in Table 10 for collections made in 1957 and 1958. Data for collections carried out before 1957 have been presented in HASL=l,2 entitled "“Envirommental Contamination from Weapon Tests". Data for all samples analyzed are presented graphically in Figure 6, The error term depicts one standard deviation due to the error in counting. - 78 -