89 23942405,/2385,, ratios of 27.5 and 33.3 found in the two deeper segments of the core are similar to several other ratios found in surface sediments of the lagoon which were collected away from the region south of Tewa Crater. 9.3-2 Northwest Lagoon Quadrant Profiles Three sediment cores were collected from this region of the lagoon (stations B-2, B-20 and B-21). The distribution of radionuclides in surface sediments (section 5) and the distribution of finely divided sediments (section 5.3) in this region of the lagoon have been discussed previously. Pulverized sediments were found at all three stations, although the radionuclide concentrations were significantly lower at Station B-21 than at B-20 and B-2. The distribution of 239+2405 > 24] Am and tected at Station B-2 is shown in Figure 23. 60 ~“Co in the sediment core col- Several features of this long core were found to be similar to features in other sediment cores collected from the northwest quadrant. The distribution of 24] Am 2394240, | , 155 Eu and 137 Cs concentrations measured in this core were very similar, except that: (1) the absolute concentrations of 137 Cs measured were lower than the by a factor of 10, and (2) the 2394240 24) Am and 155 Eu concentrations Pu concentrations measured were slightly more irregular with depth than the concentrations measured for 24 an or W95ey, In the top 11 cm of the core, the concentrations of and 239+240 Pu, 24] An, 155, 137 Cs decrease regularly with depth to 50% of their respective concentra- tions as measured in surface sediment. The sediments in this part of the core consisted of mixtures of pulverized material and Halimeda, beginning in the 8-10 cm section. In the 12-26 cm regions of the core, the concentrations of 239+240 155 Pu, 241 Am Eu and 137 Cs decreased nearly logarithmically with depth. In the 28-38 cm region of the core, the concentrations again decreased slowly