Appendix D ANALYTICAL DATA from SAMPLES of SEAWATER Duplicate samples of sea water were furnished by the NRDL and the SIO. At the HASL, each sample was filtered and th> remainder evaporated. The beta activities lated value of 4.43 « 10° (dis /min)/liter for 1 mr/hr gamma at 3 fect. However, the results do indicate that the general magnitude of this assun.ption is correct for both particulate and salt fractions were determined by counting. These data were corrected for radioactive decayon the basis of the decay curves in Reference 7. D.2 DEPTH SAMPLES Particulate salt separation and beta analysis were performed on a group of depth s»mples supplied by D.t SURFACE SAMPLES Project 2.62 (SIO). The beta analysis, corrected to H+ 24 hours, is summarized in Tables D.1, D.2, D.3, and D.4, for Shots Zuni, Flathead, Navajo, and Tewa. The sampling loca- tions were plotted on the aerial-survey isodose charts and the gamma intensity at each station was estimated by extrapolation between the isodose contours. Because the gamma dose-rate values are estimated, further ex- trapolation may contain errors. The time of gamma survey and the time of sampling do not necessarily coin- The court titne corrections for radioactive decay were made to the mean of the counting period for all samples within a group. The data from Shots Flathead and Navajo are summarized in Table D.5, and from Shot Tewa in Table D.6. These values are plotted in Figures D.2 and D.3. Activities below 10 dis/min are not particularly valid, because they correspond to counting rates below the cide, so the interviewing horizontal translation of the statistically reliable level. The surface activity for samples from Shots Flathead and Tewa are based on the average of several identical samples. The surface water mass can introduce displacement errors. activity for Station N-17, after Shot Navajo, is based on The surface activity, as beta disintegration per minute per liter, has been plotted against estimated gamma dose rate in Figure D.1. With the large variation of the observed cata, it is not possible to confirm the calcu- a single sample and maynot represent the actual surface conditions. A mixing depth of 60 meters is indicated by this data (Figure 3.26). Tages “10 Yeuld Deleted ’ 69

Select target paragraph3