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Pond 017, constructed in the fall of 2002, treats runoff from a 955 acre watershed including mine disturbance areas from the southern portion of the south extension of the permit area. The pond is located on upper Hubberson Gulch neaz the southwest comer of the south extension area. Pond 017 construction certification and "As-Built" designs were included in PR-4 submittal materials. D. Acid-forming and Toxic-forming Spoil The applicant has submitted detailed analysis of the geochemical characteristics of the overburden and interburden found in the Seneca II-W Mine permit area. Initial drilling and geochemical sampling was conducted within the baseline study area prior to initiation of operations. Additional drilling and sampling was conducted within the south extension area in 1991. Until approval of PR-3, in 2003, coal extraction was limited to the Wadge seam, and the initial baseline studies were focused on Wadge overburden assessment. Strata from the surface to immediately below the Wadge coal seam were sampled. Core holes were distributed across the Wadge recovery areas in both the original permit area and south extension azea (Exhibits 6-6 and 6-6A). PR-3 allowed for surface mining of the Sage Creek and Wolf Creek Seams, as well as the Wadge, within the South Extension area. Characterization and assessment of Sage Creek and Wolf Creek overburden, and Wolf Creek underburden was based on chip samples collected from Monitoring Well WWCU-24, which was drilled into the Wolf Creek underburden near the western boundary of the south extension area in 2001 (Exhibit 7-lA). In addition to the site specific geochemical data from WWCU-24, Sage Creek/Wolf Creek overburden chazacterization and assessment included consideration of data from the adjacent Yoast Mine permit area, for the same strata. Parameters sampled are listed in the permit application Volume 2, Tab 6. The permit application states that these parameters were used to, "document the physical and chemical properties of the overburden and underburden, to compare these properties to ground water quality, and to determine potential reclamation success." The data obtained from the geochemical analyses were compared to criteria derived from State and Federal agencies (USDA, BLM, Wyoming DEQ, and others). The criteria used for comparison and relative degrees of suitability are listed in Volume 2, Tab 6, Table 6-3. Analytical data associated with Wadge overburden and immediate underburden is presented in Tables 6-4 through 6-7, and Seneca R-W Findings Document 26 November 17, 2004 Permit Revision No. 4