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Drilling and Collection. Overburden materials are generally sampled by utilizing one or <br /> more of the following three methods; continuous cores, cuttings or chips, and highwall or <br /> outcrop grab samples. Barrett et al . (1980), Dollhopf et al . (1981 ), MDSL (1983), <br /> Harrington (1983), WDEQ (1985), and USDI-OSMRE (1985b) all recommend that a combination of <br /> continuous core and drill cuttings locations be utilized for baseline OIU studies. <br /> Continuous coring is primarily utilized during the first phase of an OIU sampling program <br /> to document structure and stratigraphy. Subsequently during Phase II, rotary drilled chip <br /> samples are preferred to confirm chemical and physical trends because sampling is faster <br /> and more economical . Barth et al . (1981) recommends chip sampling for shallow overburden <br /> or where strata is homogenous. Harrington (1983) states that overburden analyses results <br /> obtained from cores and cuttings were similar when drilling fluids and other variables <br /> were controlled. Dollhopf et al . (1981 ) relied exclusively on chip sampling for all of <br /> their selective handling studies. Peabody Coal Company (1987) showed lithologic <br /> descriptions and saturation percentages to be similar from a twinned hole location (i .e., <br /> Bore Hole 5086E was 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 <br /> push core barrel was used to collect representative samples from the unconsolidated <br /> surface while a three inch core barrel with a Chris dril bit was utilized to collect <br /> subsurface consolidated material . A 3 inch diameter core barrel as opposed to a 2-1/8 <br /> inch barrel, was utilized to minimize core loss. Soft to slightly hard sandstone was <br /> encountered at 3.6-16.0 and 22.0-24.0 feet at Site 871E. Consequently, chip samples were <br /> collected with sampling buckets by utilizing a 5$ inch Tricone rock bit. <br /> The core and chip samples were described in the field by the driller and subsequently by a <br /> soil scientist. Standard geologic description information such as lithology, color, <br /> hardness, grain size, boundary conditions, wetness, and presence of fractures, pyrites, <br /> gypsum, and carbonates were included. The chip samples and cores were packaged in 6 mil <br /> polyethylene by two foot increments and placed in standardized boxes for shipment to the <br /> lab. Once all cores were drilled, sampled, described, and boxed, they were shipped by <br /> truck to InterMountain Lab in Farmington, New Mexico. <br /> Sampling Methodology - Phase It <br /> A Phase II drilling program was implemented in August, 1987 to assess and confirm the <br /> extent of suitable, marginally suitable, and unsuitable material and to meet CMLRD hole <br /> 6-1-14 Revised 04/11/88 <br />