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• because sampling is faster and more economical. Barth et al. (1981) recommends chip sampling <br />for shallow overburden or where strata is homogenous. Harrington (1983) states that overburden <br />analyses results obtained from cores and cuttings were similar when drilling fluids and other <br />variables were controlled. Dollhopf et al. (1981) relied exclusively on chip sampling for all of their <br />selective handling studies. Peabody Coal Company (1987) showed lithologic descriptions and <br />saturation percentages to be similar from a twinned hole location (i.e., Bore Hole 5086E was <br />located less than 75 feet from Core Hole 4508E). <br />Peabody drilled and collected samples from three core holes during Phase I. A two inch push core <br />barrel was used to collect representative samples from the unconsolidated surface while a three <br />inch core barrel with a Chris drill bit was utilized to collect subsurface consolidated material. A 3 <br />inch diameter core barrel as opposed to a 2-1/8 inch barrel, was utilized to minimize core loss. Soft <br />to slightly hard sandstone was encountered at 3.6-16.0 and 22.0-24.0 feet at Site 871 E. <br />Consequently, chip samples were collected with sampling buckets by utilizing a 51/4 inch Tricone <br />rock bit. <br />The core and chip samples were described in the field by the driller and subsequently by a soil <br />• scientist. Standard geologic description information such as lithology, color, hardness, grain size, <br />boundary conditions, wetness, and presence of fractures, pyrites, gypsum, and carbonates were <br />included. The chip samples and cores were packaged in 6 mil polyethylene by two foot increments <br />and placed in standardized boxes for shipment to the lab. Once all cores were drilled, sampled, <br />described, and boxed, they were shipped bytruckto InterMountain Lab in Farmington, New Mexico. <br />Sampling Methodology -Phase II <br />A Phase II drilling program was implemented in August, 1987 to assess and confirm the extent of <br />suitable, marginally suitable, and unsuitable material and to meet CDMG hole density requirements. <br />Drill hole descriptions, chemical analyses, and textural analysis data from Phase I sampling indicate <br />lateral variability in the local depositional environment. Based upon the cropline to recovery line <br />variability, Peabody selected (meeting, G. Wendt and S. Renner, June 22, 1987 and letter G. <br />Wendt to P. O'Connor, July 6, 1987), and CDMG approved three additional sample locations to <br />accurately delineate areas of acidic and/or sodic overburden and interburden. The combined <br />Phase I/II sampling intensity for the New Horizon 2 study area is 80 acres/hole. <br />Revised 27 Aug 2002 12 <br />