6.11.3 FPDB Soil-Sampling Procedures The soil-sampling procedures employed during the ERSP were developed over a period of time by the LLL field team as part of a continuing environmental project in the Marshall Islands. The soil-sampling program began in February 1979 at Enewetak Atoll, This program was conducted by the DOE Nevada Operations Office (NV), receiving technical direction from LLL. A 50-m grid was established on each of the islands from Alice through Wilma, ie., the northwest through the northeast and east side of the atoll. Soil profile samples were collected at each 50-m grid point. All soil profile samples were collected over the following increments: 0-5, 5-10, 10-15, 15-25, 25-40, and 40-60 cm. Observations indicate that a 40-em depth encompasses most of the active root zone of the subsistence erops observed in the northern Marshall Islands. In addition, soil profiles of radionuclide concentrations provide a basis to evaluate the effectiveness of soil-removal procedures for reducing the soil radionuclides inventory and therefore the dose. A trench was dug at each 50-m grid point using a backhoe, and samples were collected down the sidewall of the trench after seraping the sidewall to avoid any possible contamination from digging. The 0-5 cm sample was collected from a surface area out to about 25 em on the side of the trench. The area was then expanded by about 10 emon each side and cleared to a depth of 5em. The upper surface (1-2 em) of this enlarged area (35 em”) was then cleared to ensure that no surface soil, or soil from a preceding increment, had fallen onto the next increment to be sampled. The next sample was then taken from the entire depth of the increment (i.e., 5-10 em) from an area about 25 em within the enlarged area. This procedure was repeated until the final increment of 40-60 em was eollected. A total of approximately 1,000 g of soil was collected for each profile increment. The soil samples were dried and ground into a fine powder in a ballmill. Samples were then analyzed by gamma spectroscopy to determine the 137Cs and 241 Am concentrations and by wet chemistry procedures to determine the concentration of 9%Sr and, in some cases, 2 »240py, Am, and 41bu. Eberline Instrument Corporation used wet chemistry procedures to determine concentrations of 90sp, 239,240 py, 24lam, and of the analyses. 24l py. The DOE/NV was responsible for the quality control aspects 6.11.4 FPDB Data Storage and Retrieval The soil concentration data from the analytical program were grouped according to the island of origin and put in a computerized data bank by DRI and supplied to LLL. into an appropriate format to proceed with the dose assessment. The data were then reduced The radionuclide concentrations as reported by DRI are in profile increments (i.e., 0-5, 5-10, 10-15, 15-25, and 25-40). For purposes of this assessment a more useful format is the activity integrated over certain depths (0-5, 0-15, and 0-40 em). After converting each profile into this format, the integrated activity for each island, or in the case of larger islands, for island subsections, is summarized. Selected portions of the FPDB results are reported in Tables 7-1, 7-2, and 7-3. Results of the dose assessment were prepared in booklet form (DOE, 1979), in side-by-side English and Marshallese text, and presented to the people of Enewetak at a meeting on Ujelang Atoll in September 1979. 6.12 SAMPLE ARCHIVING (by Paul B. Dunaway and Hollis A. Berry) In the early stages of planning for the Enewetak Radiological Support Project, it was realized that representative soil samples from Enewetak should be archived. Archived samples were retained for the following potential needs: (1) rechecking anomalous data; (2) analyzing samples for other information which might be required for later ERSP needs; (3) comparing samples with samples which might be taken in future years at Enewetak; and (4) having a record for future legal actions that might arise. Samples were retained for archiving under the following general guidelines. All samples were retained from those areas on which no remedial action was taken. In addition, the "as left" last surface samples from each cleaned area were retained. Some special samples taken from places such as Aomon Crypt were also kept. Both surface and profile samples are in the archive. The rationales for these selections are: (1) a record is needed of the condition in which untreated areas 200