Results of rock property measurements made on core samples from Yucca Mountain boreholes, Nevada Test Site, Nevada

Abstract

This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. Any use of trade names is for descriptive purposes only and does not imply endorsement by the USGS.

Air-injection testing in vertical boreholes in welded and nonwelded tuff, Yucca Mountain, Nevada

“…Flint and Flint (1990) The air-injection permeability values of the nonwelded tuff of the Paintbrush Group are as much as an order of magnitude greater than the Anderson (1994) and Flint (1990) laboratory water and airpermeability values. On the other hand, the airinjection permeability values of the Yucca Mountain Tuff are an order of magnitude smaller than the Anderson (1991) water-permeability values. These comparisons indicate that the nonwelded tuff is heterogeneous at the scale of the laboratory tests.…”

“…Anderson (1991) Table 9 presents the pneumatic-monitoring permeability values from boreholes NRG-6 and NRG-7a (E. Kwicklis, U.S. Geological Survey, written commun., 1996) and the air-injection permeability value arithmetic means and ranges.…”

“…The welded Topopah Spring Tuff water-permeability values ranged from less than 10'18 m2 to 3.9 x 10'14 m2 with an average of approximately 2.0 x 10' 15 m2. The samples analyzed by Anderson (1991) were mostly from the Topopah Spring crystal-rich nonlithophysal zone, which is a zone of increased porosity (Buesch and others, 1996) and, therefore, apparently increased matrix permeability. The water-permeability values (Anderson, 1991) of the nonwelded tuff of the Paintbrush Group included two Yucca Mountain Tuff samples, 4.2 x 10" 12 m2 and 2.5 x 10' 12 m2, and a single Pah Canyon Tuff sample, 2.0 x 10' 13 m2.…”

“…The samples analyzed by Anderson (1991) were mostly from the Topopah Spring crystal-rich nonlithophysal zone, which is a zone of increased porosity (Buesch and others, 1996) and, therefore, apparently increased matrix permeability. The water-permeability values (Anderson, 1991) of the nonwelded tuff of the Paintbrush Group included two Yucca Mountain Tuff samples, 4.2 x 10" 12 m2 and 2.5 x 10' 12 m2, and a single Pah Canyon Tuff sample, 2.0 x 10' 13 m2. Flint and Flint (1990) The air-injection permeability values of the nonwelded tuff of the Paintbrush Group are as much as an order of magnitude greater than the Anderson (1994) and Flint (1990) laboratory water and airpermeability values.…”

“…These values are in agreement with water-permeability tests (Peters, 1984) on core samples from the same boreholes. Anderson (1991) also did laboratory waterpermeability tests on core samples from boreholes UE-25a #4, #5, #6, and #7. The welded Topopah Spring Tuff water-permeability values ranged from less than 10'18 m2 to 3.9 x 10'14 m2 with an average of approximately 2.0 x 10' 15 m2.…”