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The applicant has notified all surface landowners within one-quarter (1/4) mile of the <br />disposal well of their intent to apply for a Class I nonhazardous Permit for an existing Class II <br />facility. <br />Regional Geology and Stratigraphy: Information on the subsurface strarigraphy, <br />structure resources,. and ground-water hydrology of the project area was supplied by the pemuttee. <br />The Piceance Creek Basin is a structural as well as a topographic basin, with the <br />following structural features forming the boundaries of the basin: the Douglas Creek Arch to the <br />west, the eastern Uinta Mountains and the Axial Basin Anticline to the north, the White River <br />Uplift to the east, and the Uncompahgre Uplift to the south. The basin is asymmetric and is <br />structurally deepest in the northwest where crystalline basement rocks are estimated to be 24,000 <br />feet below the surface. Four major drainages have developed in the basin: 1) the Piceance Creek <br />and the Yellow Creek drainages discharging north to the White River; and 2) the Parachute Creek <br />and the Roan Creek drainages dischazging to the south into the Colorado River. The Getty # 1- <br />7LW is located in the downstream end of the Roan Creek drainage. <br />The geologic unit immediately underlying the wellsite is the Wasatch Formation. The <br />Roan Creek alluvium appears to absent at the well site which is located on a hill. The Ohio Creek <br />Conglomerate underlies the Wasatch at a depth of about 1,OS0 feet BGS, and is a 110 foot thick <br />unit that is a highly weathered, pebbly, kaolinite rich conglomerate. The Ohio Creek <br />Conglomerate mazks the transition with the Williams Fork Formation that is the top of the <br />Mesaverde Group at approximately 1,160 feet BGS. The Williams Fork Formation at the Getty <br />well is made up of 2,610 feet of coastal, fluvial, and paludal sediments containing both lenticulaz <br />and blanket sand deposits. The paludal interval makes up the bottom 860 feet of the Williams <br />Fork Formation and contains mudstones, siltstones, sand lenses and coal layers (the Cameo Coal). <br />The Rollins Sandstone Member of the fles Formation underlies the paludal interval of the <br />Williams Fork at approximately 3,6¢0 feet BGS and is about 190 feet thick. It appears to be a fine <br />grained to course grained sandstone reservoir with quartz and calcite cementing. The Rollins is <br />underlain by a tongue of Mancos shale at about 3,810 feet. The Mancos is an interbedded <br />mudstone and marine shale (with occasional sand lenses) which overlies and underlies the <br />Cozzette and Corcoran Sandstones and acts as the principal confining mechanism. <br />The top of the upper injection zone, the Cozzette Member of the Iles Formation, is at <br />approximately 3,864 feet BGS. The Cozzette is about 212 feet thick, and is perforated from 3,911 <br />to 3,927 feet BGS in the Getty # 1-7LW. The lower part of the Cozzette is a series of shale layers. <br />The lower injection zone is the underlying Corcoran Member of the Iles Formation. The Corcoran <br />top is at 4,076 feet and it is approximately 205 feet thick with perforations from 4,07? feet to <br />4,241 feet. The Formation underlying the Corcoran Sandstone at about 4,280 feet BGS is the <br />Mancos Shale. <br />Hydrogeology: <br />Underground sources of drinking water (USDWs) aze defined in 40 CFR § 144.3 as: <br />Statement of Basis for EPA Permit No. CO 10932-04664 Page 3 of 18 <br />