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We used a Mars analog, the Chilean Atacama Desert, to simulate a drilling mission to Mars, as part of the Atacama rover astrobiology drilling study (ARADS) grant through NASA's PSTAR Program. Automated drilling from a rover platform within one meter of a conventional science dig allowed us to make a direct comparison of manned vs. unmanned data return at a potential two-million-year-old lake bed/evaporite site near Yungay Station. Science observations of soil type and biomolecule content compared well to planetary mission-type data of size distribution, cuttings angle of repose, drill telemetry, and instrument readings. Drill telemetry data taken during four companion studies allowed us to characterize soil horizons that might affect instrument results. Water signatures were encountered during a tracer study which demonstrated how much contamination is brought into a cohesive borehole by three different vectors: the drill itself, surface in-fall due to downstroke, and surface in-fall due to retraction. Water signatures were also encountered during a study of polygonal structures to interpret data variation in these large-scale soil formations also observed on Mars. Salt horizons were encountered during a biomarkers/halite transect study. Salt horizon data was also gained from a second polygon edge study in hyperarid soil, which linked lower drill torque at polygon edges with increased in-fall and mixing compared to that of polygon interiors. Characterizations of how a drill transforms and makes available subsurface information from this analog environment can help us interpret results of a drill-based mission to Mars. Results obtained in the Atacama indicate drill telemetry and cuttings offer a wealth of accurate subsurface data.