2001-12-11_PERMIT FILE - C1980005 (3)

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• However, as has already been indicated, more than ten hearths were exposed in the area to be impacted. But, rather than having to be selective in choosing which features to date, it was difficult to obtain charcoal samples from even ten hearths since many of the hearths contained little or no charcoal. This problem was compounded by the fact that a brush fire-possibly set by sheepherders-had occurred in the area. This burning is evident presently in charred roots, many of which occur sub- surface: usually shallow (top 10 an) but oftentimes extending further down as a fire followed a mot system. Radiometric Wntamination of subsurface deposits is, therefore, a distinct possibility. Ten carbon samples were forwarded to Mr. Charles S. Tucek of Radiocarbon, Ltd., for radiocarbon determinations. The results are presented in Table 6. Of the ten samples, only three prehistoric dates were obtained. Six of the rema;n~nq seven dates are modern (i.e. usually 200 years old or less); the seventh sample was not run. bccept for two samg~les frram a • stratigraphic profile (RL1429 and RL1430) , all of the carbon sales were obtained from an obvious cultural mntext, i.e. from within a prehistoric hearth. The plurality of recent dates seems to substantiate the possi- bility of contamination. Table 6. Radiocarbon Dates from Site SRT139 Radiocarbon, Ltd. Lab No. Sample Designation 8 of "Modern" Radiocarbon age, years, B.P. P'II~.SCP. mrr. AD/BC Date RL - 1426 F5139-2-1-2 > 100 b7odern - RL - 1427 FS139-3-2-3 86.9 + 2.5 1130 + 230 AD 850 + 220 RL - 1428 FS139-3-3-2 99.2 _+ 1.2 Modern < AD 1530 RL - 1429 FS139-3-6-1 ~ 100 Pbdern - RL - 1430 FS139-3-6-2 97.6 + 2.7 Modern ~ AD 1300 RL - 1431 FS139-6-3-1 ~ 100 Modern - • RL - 1432 FS139-7-2-7 99.5 + 1.2 Modern - RL - 1434 FS139-7-11-1 48.0 + 1.1 5900 +_ 180 4800 BC +_ 220 RL - 1435 F5139-7-16-1 44.9 + 1.0 6430 + 180 'r 5300 BC 39