Geohydrologic data for test well UE-25p No. 1, Yucca Mountain area, Nye County, Nevada

The following data are given for test well UE-25p No. 1: drilling operations, lithology, availability of borehole geophysical logs, water levels, water chemistry, pumping tests, borehole-flow survey, and packer-injection tests. The well is one of a series of test wells drilled in and near Yucca Mountain adjacent to the Nevada Test Site, Nye County, Nevada, in cooperation with the US Department of Energy. These investigations are part of the Nevada Nuclear Waste Storage Investigations to identify suitable sites for underground storage of high-level radioactive wastes. Test well UE-25p No. 1 was drilled to a total depth of 1805 meters. To a depth of 1244 meters, the rocks are predominantly ashflow tuffs of Tertiary age. From 1244 to 1805 meters, the rock is dolomite of Paleozoic age. The composite static water level was approximately 381 meters below land surface for the Tertiary section and 361 meters for the Paleozoic section. Hydrologic tests were performed on the well during two different periods. The Tertiary section was tested after the well was drilled to 1301 meters, and the Paleozoic section was tested after completion of drilling. A pumping test of the Tertiary section showed a maximum drawdown of about 33.7 meters after pumping for 3150 minutes at 22 liters per second. Pumping of the Paleozoic section showed an apparent maximum drawdown of 9.3 meters after pumping for 6080 minutes at 31.5 liters per second. During the first 50 minutes of the pumping test, the discharge temperature increased from about 30 to 560C. A borehole-flow survey showed that, for the Tertiary section of the hole, about 58% of the water withdrawn from the well came from the depth interval from 469 to 501 meters. For the Paleozoic section, 75% of the water withdrawn from the well came from the depth intervals from 1340 to 1362 meters and from 1515 to 1551 meters. 9 references, 49 figures, 6 tables