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li <br /> <br />sampling is faster and more economical. Barth et al. (1981) recommends chip sampling for shallow <br />overburden or where strata is homogenous. Harrington (1983) states that overburden analyses <br />results obtained from cores and cuttings were similar when drilling fluids and other variables were <br />controlled. Dollhopf et al. (1981) relied exclusively on chip sampling for all of their selective handling <br />studies. Peabody Coal Company (1987) showed lithologic descriptions and saturation percentages <br />to be similar from a twinned hole location (i.e., Bore Hole 5086E was located less than 75 feet from <br />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 inch <br />core barrel with a Chris drill bit was utilized to collect subsurface consolidated material. A 3 inch <br />diameter core barrel as opposed to a 2-1/8 inch barrel, was utilized to minimize core loss. Soft to <br />slightly hard sandstone was encountered at 3.8-16.0 and 22.0-24.0 feet at Site 871 E. Consequently, <br />chip samples were collected with sampling buckets by utilizing a 5114 inch Tricone 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 by truck to 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. Wendt <br />to P. O'Connor, July 8, 1987), and CDMG approved three additional sample locations to accurately <br />delineate areas of acidic and/or sodic overburden and interburden. The combined Phase 1/II <br />sampling intensity for the New Horizon 2 study area is 80 acres/hole. <br />Revised 9/99 2.04.6-11 <br />