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Sampling Procedures. Geophysical and geochemical analysis of all strata above the lowest coal <br />seam to be mined (Wadge overburden) and the stratum immediately below the lowest coal <br />seam to be mined (Wadge underburden) were performed in 1974, 1980, 1981, and 1992. The <br />sampling program consisted of drilling a total of 17 2-1/8-inch diameter continuous core holes <br />and 2 4-3/4-inch diameter combination rotary drilled chip and continuous core sample holes at <br />various locations to be disturbed by mining. Survey information for these 19 sites is listed in <br />Table 6-1. The locations of these holes are shown on Exhibits 6-6 and 6-6A and the lithologic <br />logs are presented in Appendix 6-1. <br />Two drilling mediums, a bentonite-water solution and air, were used to lift cuttings from the <br />borehole during core collection. Zinc and copper base drill stem joint lubricants were used <br />during 1974, 1980, and 1981 to reduce excessive drill stem wear and torque. A KOPR-KOTE <br />drill collar and tool joint lubricant (lead free) produced by Jeb-Cube, Houston, Texas, was used <br />during 1991. These compounds were necessary for trouble-free core and bore hole drilling, but <br />may have unavoidably contaminated a portion of the samples. <br />Overburden cuttings (chip samples) were collected exclusively with air from sites 3080C and <br />315X. Chip samples were collected on two-foot vertical increments from the soil surface to <br />the top of the coal. Core samples were collected below the Wadge coal seam. Chip samples <br />were collected with sampling buckets by using a 4-3/4-inch Tricone rock bit. Chip samples <br />were composited in the field according to the lithologic and stratigraphic descriptions prepared <br />by the soil scientist. <br />The core samples were packaged in four-mil polyethylene by two-foot increments and placed in <br />standardized boxes for shipment to the lab. Once all chip samples and cores were drilled, <br />sampled, described, and boxed, they were shipped by truck to Peabody Central Laboratory in <br />Freeburg, Illinois or InterMountain Lab in Sheridan, Wyoming. <br />The overburden cuttings (chip samples) collected for the Sage Creek/Wolf Creek program were <br />collected using air andlor foam during drilling. Drill cuttings were collected at two•foot intervals from <br />the WWCU-24 well for logging purposes. These were essentially chip samples collected using a screen <br />which allowed the water to drain out. Cuttings were composited in the field for 5 consecutive sample <br />intervals, which provided an overall 10-foot sample interval for material to be laboratory analyzed. The <br />composite samples were placed into double plastic bags, labeled and sealed. The Wadge coal was <br />observed from 185 to 798 feet bgs in WWCU-24. The composite samples selected for analytical <br />testing were beneath the Wadge coal. Assessment of the Wadge overburden was completed for the <br />existing permit as presented previously in this Tab. The overburden interval (less coal intervals) <br />between the base of the Wadge coal and the bottom of borehole WWCU-24 is 218 feet, which is <br />approximately 34 feet below the base of the Wolf Creek coal. A total of 21 composite samples were <br />hand transported to ACZ Laboratories for analysis. <br />PR03 16 Revised 01 /OZ <br />