ER-12-1 completion report

Abstract

Portions of thisDrilling problems included hole deviation and hole instability that prevented the timely completion of this borehole. Drilling methods used include rotary tri-cone and rotary hammer drilling with conventional and reverse circulation using aidwater, aidfoam (Davis mix), and bentonite mud.Geologic cuttings and geophysical logs were obtained from the well. The rocks penetrated by the ER-12-1 drillhole are a complex assemblage of Silurian, Devonian, and Mississippian sedimentary rocks that are bounded by numerous faults that show substantial stratigraphic offset.The final 7.3 m (24 ft) of this hole penetrated an unusual intrusive rock of Cretaceous age. The geology of this borehole was substantially different from that expected, with the Tongue Wash Fault encountered at a much shallower depth, paleozoic rocks shuffled out of stratigraphic sequence, and the presence of an altered biotite-rich microporphyritic igneous rock at the bottom of the borehole.Conodont CAI analyses and rock pyrolysis analyses indicate that the carbonate rocks in ER-12-1, as well as the intervening sheets of Eleana siltstone, have been thermally overprinted following movement on the faults that separate them. The probable source of heat for this thermal disturbance is the microporphyritic intrusion encountered at the bottom of the hole, and its age establishes that the major fault activity must have occurred prior to 102.3+0.5 Ma (middle Cretaceous).Geophysical logs run in the saturated and unsaturated sections of the borehole were invaluable for interpretation of stratigraphy and structure. Problems encountered during logging were lack of service tables for stacked logs, lack of calibration tables for the ER-12-1 hole size, and lack of written procedures for running these logs in the field. Hydrologic investigations consisted of water level monitoring, flow logging, aquifer tests, and drill-stem tests. The results indicate that the static composite fluid level in well ER-12-1 was 469 m ( 1540 ft) below land surface. Drill-stem tests and flow logs determined that the lower two intervals in the well are underpressured relative to the upper zones by approximately 396 m (1 300 ft). Aquifer tests, drill-stem tests, and flow logs determined that the transmissivity of the well ranged from 7.5 x m2/s, with the most transmissive zone being 518 to 555 m (1700 to 1820 ft) below land surface followed by the 9 14 to 963 m (3000 to 3 160 ft). The pressure differential between these zones allowed for substantial crossflow to occur while the well was open.to 4 x Two types of geochemical samples were acquired from this well. Water quality samples taken during drilling and testing indicated very few problems associated with the well. Those identified consisted of elevated quantities of volatile and semivolatile organics (sample 10006) and metals (sample 10007) associated with the drilling process. Geochemical characterization samples were taken only from the uppermost zone, 518 to 555 m (1700 to 1820 ft). The results from this sample vii indica...

Phase I Contaminant Transport Parameters for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat/Climax Mine, Nevada Test Site, Nye County, Nevada, Revision 0

“…Eleana Formation as originally defined by Poole et al (1961) was partitioned by Cashman and Trexler (1991) Fracture-filling minerals in the UCCU, as reported in various lithologic logs (BN, 2004;Russell et al, 1996;Fernald et al, 1975) include quartz, calcite, clay and rare pyrite, and trace MnO 2 .…”

“…Both the completion casing string and the production string for this well are carbon steel. Although five sliding sleeves exist in this well (Russell et al, 1996), only the upper sleeve (535.5 to 536. of the carbon-steel casing of this well. A trend of decreasing pH (8.9 to 6.4) and increasing temperature (22.8 to 28.3 °C) with depth was observed.…”

A Hydrostratigraphic Model and Alternatives for the Groundwater Flow and Contaminant Transport Model of Corrective Action Unit 97: Yucca Flat-Climax Mine, Lincoln and Nye Counties, Nevada

“…Foreland imbricate faults associated with the Belted Range thrust fault are exposed in the Eleana Range and Mine Mountain (Gibbons et al, 1963;Orkild, 1963;Orkild, 1968; and have been penetrated in UGTA Well ER-12-1 (Russell et al, 1996). These imbricate faults form a complex series of stacked thrust slices involving mostly Devonian carbonate and Mississippian siliciclastic rocks within the footwall of the Belted Range thrust fault.…”

Corrective Action Investigation Plan for Corrective Action Unit 99: Rainier Mesa/Shoshone Mountain, Nevada Test Site, Nevada with Errata and ROTC 1, Rev. No. 0

“…Well ER-19-1, from Russell et al (1996) for Well ER-12-1, and from Russell et al (2003) for the groundwater impounded within the N-and T-Tunnels. Ground-water flow through the fractured tuffs at Rainier Mesa were investigated by Russell et al (1987), and perched groundwater at Rainier Mesa was investigated by Thordarson (1965).…”

“…These groundwater characterization samples are analyzed for a suite of radionuclides. These data are included in a series of well completion reports (e.g., Smith, 1993b;Russell et al, 1996;IT, 1995), as well as annual reports and well-specific letter reports published by LLNL and LANL (Rose, 2003;Aldrich, 2003).…”