Earth sciences waste disposal investigations, July--December 1965

Ground-water contribution to dose from past Hanford Operations

“…The interpreted distribution of gross beta contamination in the unconfined aquifer changed only minor amounts from July 1966 through December 1974 (Eliason 1967b;Kipp 1973aKipp , 1973bRaymond et al 1976). cautioned that concentration contours presented in the report should not be interpreted as indicating that no radioactivity was present in the ground water beyond the outermost boundary of the interpreted plume.…”

“…Stevens recorders were used to collect information on continuous water-level variations in some wells (Raymond 1960). This type of information was most important in wells near the Columbia River and near effluent disposal facilities such as the 100-N Area (Eliason 1967a). …”

“…This interpretation was based on the same reporting levels (contours) and detection Eliason (1966a) interpreted the extent of contamination to be larger, based on detection of gross beta in several additional wells.…”

“…The interpreted distribution of average gross beta contamination in the aquifer was slightly different from the previous reporting period. Eliason (1966b) included a discussion of travel-time predictions for beta emitters from the 216-A-10 crib downgradient to well 699-34-39A . In late 1962, an increase of beta activity discharged to the A-10 crib for a 2-month period was observed.…”

“…As with gross beta monitoring results for 1965 (Figure 6.20), the distribution of average tritium concentrations in the unconfined aquifer from July through December 1965 (Figure 6. 29) reported by Eliason (1966a) was considerably different from that during the previous reporting period, although the same contour intervals and detection limit (2 pCi/L) were used. The expanded zone of tritium contamination was a based on measurements showing tritium ievels slightly above the detection limit in several additional wells.…”