Two 5-cm-long whole rounds were taken adjacent to interstitial water whole rounds, in those sections of the core judged most intact (Samples 205-1255A-2R-2, 43-48 cm, and 3R-2, 127-133 cm). Two samples (5 cm3 each) were frozen at -80°C immediately after collection for postcruise ATP quantification and DNA assessment. Small samples (0.5 cm3) from the same locations were fixed in 2% formalin solution for postcruise cell counting. Twice during coring, 40-mL samples of drilling fluid were collected as the fluid escaped the core liner, and these samples were also frozen promptly at -80°C; evaluation of the drilling fluid will constrain estimates of core contamination in terms of real cell numbers.
The chemical tracer was not deployed during coring in Hole 1255A, but fluorescent microspheres were deployed in every core and counted using epifluorescence microscopy, as described in "Microbiology" in the "Explanatory Notes" chapter. No microspheres were found in interior or exterior core samples, and the arrival of microspheres to the sampling sites is uncertain because of low recovery. Postcruise microbiological work will take this uncertainty into consideration.