Dr. Robert Holt

Areas of Expertise

Geological sequestration of CO2, impact of wetted-phase structure on geophysical properties in porous media, non-ideal transport processes in porous and fractured media, non-continuum approaches for modeling multiple-phase flow and transport, geologic controls on hydraulic properties and flow and transport processes, flow and transport processes in heterogeneous saturated and unsaturated porous and fractured media, limitations of parametric models in hydrology, including both deterministic and stochastic models, geologic and hydrogeologic characterization for nuclear and hazardous waste disposal

Recent Projects




Impact of capillary heterogeneity on CO2 dissolution in porous media

Sequestered CO2 may leak along annular spaces of old boreholes. Capillary heterogeneity controls the spatial distribution of CO2 gas in shallow aquifers and its dissolution rate.





Influence of trapped and compressed gasses in shallow mudrocks

We have found evidence of a trapped and compressed gas phase in mudrocks from New Mexico, Texas, and Mississippi. In all cases, the mudrocks are overlain by a shallow aquifer, and some are underlain by deeper aquifers. We find that the average capillary pressure (the difference in the pressures between the gas and water phases) range from about 2 to 15 MPa. When these rocks are drilled, the gas phase equilibrates with the atmosphere, and the capillary pressure drops, sometimes leading to the development of fully saturated conditions around the borehole. Trapped and compressed gases in these rocks prevent them from fully wetting and can preclude groundwater flow across the units. We are studying the physics driving this phenomena and its potential impact on recharge, flow, and transport processes in the shallow subsurface.



Geologic and hydrogeologic characterization for nuclear and hazardous waste disposal

We conduct a variety of site characterization studies at low-level and transuranic-level radioactive waste disposal sites. These studies focus on geologic and hydrogeologic characterization of low-permeability media and flow and transport processes in the subsurface.


Publications

Yang, C., Romanak, K., Hovorka, S.D., Holt, R.M., Lindner, J., Trevino, R., 2013. Near-Surface Monitoring of Large-Volume CO2 Injection at Cranfield: Early Field Test of SECARB Phase III. SPE Journal, 18(3): pp. 486-494.

Bowman, D. O., R. M. Roberts, and R. M. Holt, 2012, "Generalized Radial Flow in Synthetic Flow Systems," Ground Water. doi: 10.1111/j.1745-6584.2012.01014.x.

Holt, R. M., and D. W. Powers, 2011, "Synsedimentary Dissolution Pipes and the Preservation of Ancient Bacteria and Cellulose," Geological Society of America Bulletin, Volume 123, Issue 7-8, July 2011, Pages 1513-1523, doi:10.1130/B30197.1

Hovorka, S. D., T. A. Meckel, R. H. Trevino, J. Lu, J.-P. Nicot, J.-W. Choi, D. Freeman, P. Cook, T. M. Daley, J. B. Ajo-Franklin, B. M. Freifeild, C. Doughty, C. R. Carrigan, D. La Brecque, Y. K. Kharaka, J. J. Thordsen, T. J. Phelps, C. Yang, K. D. Romanak, T. Zhang, R. M. Holt, J. S. Lindler, and R. J. Butsch, 2011, "Monitoring a large volume CO2 injection: Year two results from SECARB project at Denbury's Cranfield, Mississippi, USA," Energy Procedia , vol. 4, pp. 3478-3485, dx.doi.org/10.1016/j.egypro.2011.02.274.

Holt, R. M., and D. W. Powers, 2010, "Evaluation of Halite Dissolution at a Radioactive Waste Disposal Site, Andrews County, Texas," Geological Society of America Bulletin, v. 122, no. 11-12, p. 1989-2004, doi:10.1130/B30052.1.

Holt, R. M., 2008, review of "Unsaturated-Zone Modeling: Progress, Challenges, and Applications [Eds. R.A. Feddes, G.H. de Rooij, and J.C. van Dam. Kluwer Academic. 2004. 364 pp. $138.00. ISBN-10: 1402029172. ISBN-13: 9781402029172.]," Vadose Zone Journal, Vol. 7, 392-393, doi:10.2136/vzj2006.0162br.

Powers, D.W., and Holt, R.M., 2008, "Lessons from early site investigations at the Waste Isolation Pilot Plant," in Rempe, N.T., ed., Deep Geologic Repositories: Geological Society of America Reviews in Engineering Geology, v. XIX, p. 83-97, doi: 10.1130/2008.4019(09).

Hovorka, S. D., R. M. Holt, and D. W. Powers, 2007, "Depth Indicators in Permian Basin Evaporites," in B. C. Schrieber, S. Lugli, and M. Babel (eds), Evaporites Through Space and Time, Geological Society, London, Special Publications, vol. 285, p. 301-330.

Holt, R. M., and D. W. Powers, 2006, "Halite Depositional Cycles in the Upper Permian Salado Formation," in Raatz, B., L. Land, and P. Boston (eds.), New Mexico Geological Society Guidebook, 57th Field Conference, Caves and Karst of Southeastern New Mexico, p. 78-80.

Powers, D. W., R. M. Holt, R. L. Beauheim, and R. G. Richardson, 2006, "Advances in Depositional Models of the Permian Rustler Formation, Southeastern New Mexico," in Raatz, B., L. Land, and P. Boston (eds.), New Mexico Geological Society Guidebook, 57th Field Conference, Caves and Karst of Southeastern New Mexico, p. 267-276.

Powers, D. W., R. L. Beauheim, R. M. Holt, and D. L. Hughes, 2006, "Evaporite Karst Features and Processes at Nash Draw, Eddy County, New Mexico," in Raatz, B., L. Land, and P. Boston (eds.), New Mexico Geological Society Guidebook, 57th Field Conference, Caves and Karst of Southeastern New Mexico, p. 253-265.

Holt, R.M., R.L. Beauheim, and D.W. Powers, 2005, "Predicting Fractured Zones in the Culebra Dolomite," in B. Faybishenko, P. Witherspoon, J. Gale, and G.S. Bodvarsson, (eds.), Dynamics of Flow and Transport in Fractured Rock, AGU Geophysical Monograph 162, American Geophysical Union, Washington, D.C., 103 - 115.

Baker, K., T. McLing, L. Street, A. Shafer, S. Ansley, L. Hull, and R. M. Holt, 2005, "A Research Park for Studying Processes in Unsaturated Fractured Media," Eos Transactions, AGU, Washington, D.C., Vol. 86, No. 2, 2005, pp. 15, 19.

Holt, R. M., and M. Nicholl, 2004, "Uncertainty in Vadose Zone Flow and Transport Prediction," Vadose Zone Journal, Vol. 3, No. 2, pp. 480-484.

Holt, R. M., J. L. Wilson, and R. J. Glass, 2003, "Error in Unsaturated Stochastic Models Parameterized with Field Data, Water Resources Research, Vol. 39, No. 2, 1028, doi:10.1029/2001WR000544.

Holt, R. M., R. J. Glass, J. M. Sigda, and E. D. Mattson, 2003, "Influence of Centrifugal Forces on Phase Structure in Partially Saturated Media," Geophysical Research Letters, Vol. 30, No. 13, 1692, doi:10.1029/2003GL017340.

Powers, D.W.; Holt, R.M.; Beauheim, R.L.; and McKenna, S.A., 2003, "Geological factors related to the transmissivity of the Culebra Dolomite Member, Permian Rustler Formation, Delaware Basin, southeastern New Mexico," in Johnson, K.S.; and Neal, J.T. (eds.), Evaporite karst and engineering/environmental problems in the United States: Oklahoma Geological Survey Circular 109, p. 211-218.

Holt, R. M., J. L. Wilson, and R. J. Glass, 2002, "Spatial Bias in Field-Estimated Unsaturated Hydraulic Properties," Water Resources Research, Vol. 38, No. 12, 1311, doi:10.1029/2002WR001336.

Powers, D.W., and Holt, R.M., 2000, "The Salt that Wasn't There: Mudflat Facies Equivalents to Halite of the Permian Rustler Formation, Southeastern New Mexico," Journal of Sedimentary Research, Vol. 70, No. 1, pp. 29-36.

Powers, D.W., and Holt, R.M., 1999, "The Los Medaños Member of the Permian (Ochoan) Rustler Formation," New Mexico Geology, Vol. 21, No. 4, pp. 97-103.

Holt, R. M., and D. W. Powers, 1993, "Summary of Delaware Basin-End Stage Deposits," in D. W. Love, J. W. Hawley, B. S. Kues, J. W. Adams, G. S. Austin, and J. M. Barker (eds.), New Mexico Geological Society Guidebook, 44 th Field Conference, Carlsbad Region, New Mexico and West Texas, p. 90-92.

Powers, D. W., and R. M. Holt, 1993, "The Late Cenozoic Gatuna Formation of Southeastern New Mexico," in D. W. Love, J. W. Hawley, B. S. Kues, J. W. Adams, G. S. Austin, and J. M. Barker (eds.), New Mexico Geological Society Guidebook, 44th Field Conference, Carlsbad Region, New Mexico and West Texas, p. 271-282.

Beauheim, R. L., and R. M. Holt, 1990, "Hydrology of the WIPP Site," Geological and Hydrological Studies of Evaporites in the Northern Delaware Basin for the Waste Isolation Pilot Plant (WIPP), D. W. Powers, R. M. Holt, R. L. Beauheim, and N. Rempe, (eds.), Geological Society of America Fieldtrip Guidebook 14, pp. 131-179.

Holt, R. M., and D. W. Powers, 1990, "Halite Sequences within the Later Permian Salado Formation in the Vicinity of the Waste Isolation Pilot Plant, Southeastern New Mexico," Geological and Hydrological Studies of Evaporites in the Northern Delaware Basin for the Waste Isolation Pilot Plant (WIPP), D. W. Powers, R. M. Holt, R. L. Beauheim, and N. Rempe, (eds.), Geological Society of America Fieldtrip Guidebook 14, pp. 45-78.

Holt, R. M., and D. W. Powers, 1990, "The Late Permian Dewey Lake Formation at the Waste Isolation Pilot Plant," Geological and Hydrological Studies of Evaporites in the Northern Delaware Basin for the Waste Isolation Pilot Plant (WIPP), D. W. Powers, R. M. Holt, R. L. Beauheim, and N. Rempe, (eds.), Geological Society of America Fieldtrip Guidebook 14, pp. 107-129.

Powers, D. W., and R. M. Holt, 1990, "Sedimentology of the Rustler Formation Near the Waste Isolation Pilot Plant (WIPP) Site," Geological and Hydrological Studies of Evaporites in the Northern Delaware Basin for the Waste Isolation Pilot Plant (WIPP), D. W. Powers, R. M. Holt, R. L. Beauheim, and N. Rempe, (eds.), Geological Society of America Fieldtrip Guidebook 14, pp. 79-106.

Holt, R. M., and D. W. Powers, 1987, "The Permian Rustler Formation at the WIPP Site, Southeastern New Mexico," Geology of the Western Delaware Basin, West Texas and Southeastern New Mexico, El Paso, D. W. Powers and W. C. James, (eds.), El Paso Geological Society Guidebook 18, pp. 140 148.

Powers, D. W., R. M. Holt, and J. M. Hoffer, 1987, "Preliminary Studies of Near-Surface Sediments, Salt Flat Graben, West Texas," Geology of the Western Delaware Basin, West Texas and Southeastern New Mexico, El Paso, D. W. Powers and W. C. James, (eds.), El Paso Geological Society Guidebook 18, pp. 184 194.

Reports

Holt, R. M., 2014, "Hydraulic Isolation of the 325 Sand," Appendix I, Geology Report, Part III, 3D3, Revision 2, Consolidated Application, submitted to TCEQ.

Holt, R. M., and B. Dudley, 2014, "Alternative Liner Demonstration for the Post Oak Landfill," Part III, 3D3, Revision 2, Consolidated Application, submitted to TCEQ.

Blainey, J. B., G. E. Grisak, J. F. Pickens, and R. M. Holt, 2012 "OAG Groundwater Model Update with Sensitivity Analysis, Prepared for Waste Control Specialists, March 16, 2012.

Ewing, J. E., V. A. Kelly, T. L. Jones, T. Yan, A. Singh, D.W. Powers, R. M. Holt, and J. M. Sharp, 2012, "Final Groundwater Availability Model Report for the Rustler Aquifer," Prepared for the Texas Water Development Board, P.O. Box 13231, Capitol Station, Austin, TX 78711-3231.

Griffith, C., and R.M. Holt, 2012, "Annual Report for Compact Waste Disposal Facility Liner and Cover Monitoring System Instrumentation, December 2012," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Griffith, C., and R.M. Holt, 2012, "Final Report for Federal Waste Disposal Facility Liner and Cover Monitoring System Instrumentation, February 2012," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Griffith, C., G. Grisak J, and R.M. Holt, 2012, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads, April 2012," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Griffith, C., G. Grisak J, and R.M. Holt, 2012, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads, October 2012," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Blainey, J. B., G. E. Grisak, J. F. Pickens, and R. M. Holt, 2011, " OAG Groundwater Model Update," in Appendix 1 of Radioactive Material License No. R04100 CN600616890 / RN101702439 Updated Performance Assessment for the Low-Level Waste Facility, Submitted to the Texas Commission on Environmental Quality, September 2, 2011.

Singh, A., G. F. Martinez, and R. M. Holt, 2012, "HYDRUS 2-D Infiltration Model Scenarios Incorporating Measured Head and Gradient in the 225-Foot Zone," Prepared for Waste Control Specialists, March 30, 2012.

Blainey, J. B., J. F. Pickens, G. E. Grisak, and R. M. Holt, 2011, "OAG Groundwater Flow Velocities and Particle Tracks at the WCS Site, Andrews County, Texas," Prepared for Waste Control Specialists, December 12, 2011.

Griffith, C., and R. M. Holt, 2011, "Draft Report for Federal Waste Disposal Facility Liner and Cover Monitoring System Instrumentation, December 2011," Prepared for Waste Control Specialists, LLC, December 6, 2011.

Griffith, C., R. M. Holt, and S. Cook, 2011, "Report for Compact Waste Disposal Facility Liner and Cover Monitoring System Instrumentation, October 2011," Prepared for Waste Control Specialists, LLC, October 14, 2011.

Griffith, C., R.M. Holt, J. Pickens, and G. Grisak, 2011, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads, April 2011," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Griffith, C., R.M. Holt, J. Pickens, and G. Grisak, 2011, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads, October 2011," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Grisak, G.E., R.M. Holt and N.A. Baker, 2011, "OAG Water Levels: Empirical and Modeled Relationships between Precipitation and Infiltration," Prepared for Waste Control Specialists, LLC, February 21, 2011.

Holt, R.M., J.S. Kuszmaul, D.W. Powers, and E.E. Hughes, 2011, Subsurface Discontinuity Mapping for the Federal Waste Disposal Facility and Compact Waste Disposal Facility Landfills," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on September 26, 2011.

Sigda, J., M-C Leroy, R. M. Holt, D. W. Powers, and G. Grisak, 2011, "2011 Logging of Neutron Tubes at the Federal Waste Facility," Prepared for Waste Control Specialists, LLC, December 6, 2011.

Sigda, J., M-C Leroy, R. M. Holt, and G. Grisak, 2011, "Data Report for 2011 Logging of Neutron Tubes at the Compact Waste Facility," Prepared for Waste Control Specialists, LLC, October 17, 2011.

Sigda, J., M-C Leroy, R. M. Holt, D. W. Powers, and G. Grisak, 2011, "2011 Logging of Neutron Tubes at the Compact Waste Facility and the Federal Facility Waste Disposal Facility and Calibration Tubes at the RCRA Facility," Prepared for Waste Control Specialists, LLC, December 28, 2011.

Singh, A., G. F. Martinez, and R. M. Holt, 2011, "Infiltration Modeling in HYDRUS 2-D," in Appendix 2 of Radioactive Material License No. R04100 CN600616890 / RN101702439 Updated Performance Assessment for the Low-Level Waste Facility, Submitted to the Texas Commission on Environmental Quality, September 2, 2011.

Singh, A., G. F. Martinez, and R. M. Holt, 2011, "Updated Infiltration Modeling in HYDRUS 2-D," in Appendix 2 of Radioactive Material License No. R04100 CN600616890 / RN101702439 Updated Performance Assessment for the Low-Level Waste Facility, Submitted to the Texas Commission on Environmental Quality, October 17, 2011.

Sigda, J., R.M. Holt, B.C. Griffith, J.F. Pickens and G.E. Grisak, 2011, "Evaluation of 2010 Neutron Logs for Soil Moisture Changes in the Vicinity of the Byproduct Landfill and at B-130, B-131, and B-132," Prepared for Waste Control Specialists, LLC, January 4, 2011.

Griffith, C., R.M. Holt, J. Pickens, and G. Grisak, 2010, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads, October 2010," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Holt, R.M., G.E. Grisak, J.F. Pickens, D.W. Powers, J. Kuszmaul, E. E. Hughes, C. Griffith, S.L. Cook, 2010, "Conceptual Model Report," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on June 24, 2010.

Holt, R.M., C. Griffith, J. Pickens and G. Grisak, 2010, "Semi-Annual Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Holt, R.M. J.S.Kuszmaul, E. Hughes, and D.W. Powers, 2010, "Subsurface Discontinuity Mapping Plan for the Federal Waste Disposal Facility and Compact Waste Disposal Facility Landfills," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on November 10, 2010.

Kuszmaul, J. S., R. M. Holt, E. Hughes, and D.W. Powers, 2010, "Discontinuity Mapping in the Byproduct Material Landfill Excavation at the WCS Site," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on November 10, 2010.

Sigda, J.M., R.M. Holt, C. Griffith, G. Grisak, and J. Pickens, 2010, "Evaluation of 2009 Neutron Logs for Soil Moiisture Changes in the Vicinity of the Byproduct Landfill and at B-130, B-131, and B-132," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on January 4, 2010.

Blainey, J.B., J.M. Sigda, J.F. Pickens, G.E. Grisak, and R.M. Holt, 2009, "Groundwater Model of the OAG for the Waste Control Specialists Site, Andrews County, Texas," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on August 11, 2009

Blainey, J.B., R.M. Holt, and J.F. Pickens, 2009, "Geostatistical Analysis of the Top of the Dockum Red Beds at the Waste Control Specialists Site, Andrews County, Texas," Prepared for Waste Control Specialists LLC, Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, Texas Commission on Environmental Quality, on June 3, 2009.

Grisak, G.E., N.A. Baker, and R.M. Holt, 2009, "Chloride Measurements in Sediments and Rock at the WCS Facility, Andrews County, Texas," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on February 27, 2009.

Holt, R.M., B.C. Griffith, J. Sigda, J.F. Pickens, and G.E. Grisak, 2009, "Monitoring and Data Evaluation Plan for Soil Moisture Monitoring in the Vicinity of the Byproduct Landfill and at B-130, B-131, and B-132," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on December 1, 2009.

Holt, R.M., B.C. Griffith, J.F. Pickens, G.E. Grisak, E. Hughes, J.M. Hubbell, 2009, "Data Report for Waste Control Specialists LLC Instrumentation Arrays at the B-130, B-131, and B-132 Well Pads," Submitted as an attachment to a letter from Tim Greene, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on November 2, 2009.

Holt, R.M., J.F. Pickens, G.E. Grisak, and B.C. Griffith, 2009, "Subsurface Hydrogeologic Properties at the WCS Site, Andrews County, Texas," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on July 24, 2009.

Holt, R.M., J.F. Pickens, and E. Jennrich, 2009, "Reconfiguration of the Northern Boundaries of Compact and Federal Facility Low-Level Radioactive Waste Disposal Facilities", Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas, Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, P.E., Texas Commission on Environmental Quality, June 3, 2009.

Pickens, J.F., G.E. Grisak, T.F. Dale, E.E. Hughes, R.M. Holt, and D.W. Powers, 2009, "Evaluation of OAG Groundwater Occurrence in the Vicinity of the Byproduct landfill," Submitted as an attachment to a letter from William P. Dornsife, WCS, to Dr. Gary L. Smith, Texas Commission on Environmental Quality, on May 5, 2009.

Pickens, J.F., G.E. Grisak, G. Davidson, R.M. Holt, and E.E. Hughes, 2009, "Tracer Studies and Groundwater Monitoring Network in the OAG at the WCS Site, Andrews County, Texas," Report prepared for Waste Control Specialists LLC, Submitted as an attachment to a letter from William P. Dornsife, WCS, to Susan Jablonski, P.E., Texas Commission on Environmental Quality, on July 9, 2009.

Holt, R.M., E. Hughes, 2008, "Report on activities to satisfy byproduct radioactive material license conditions 41A, 41C and 43," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Holt, R.M., E. Hughes, 2008, "Report on hydrologic properties and conditions at the BPMP boreholes," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Holt, R.M., E. Hughes, and J. M. Hubbell, 2008, "In Situ hydrogeologic conditions determined from core samples collected in the vicinity of the Federal Waste Landfill and a playa north of the Federal Waste Landfill at the Waste Control Specialists Site, Andrews County, Texas," Prepared for Waste Control Specialists LLC, P.O. Box 1129, Andrews, Texas.

Holt, R. M., and D. W. Powers, 2007, "Evaluation of Halite Dissolution in the Vicinity of Waste Control Specialists Disposal Site, Andrews County, TX, March 2007" in Application for License to Authorize Near-Surface Land Disposal of Low-Level Radioactive Waste, Revision 12 c, Volume 12, Appendix 2.6.1, Attachment 4-2, submitted to the Texas Commission of Environmental Quality, 158 p.

Holt, R. M., and D. W. Powers, 2007, "Report on Mapping of a Trench Through Pedogenic Calcrete (Caliche) across a Drainage and Possible Lineament, Waste Control Specialists Disposal Site, Andrews County, TX" in Application for License to Authorize Near-Surface Land Disposal of Low-Level Radioactive Waste, Revision 12 c, Volume 12, Appendix 2.6.1, Attachment 4-4, submitted to the Texas Commission of Environmental Quality, 30 p.

Holt, R. M., and L. Yarbrough, 2003, "Addendum 2 to Estimating Base Transmissivity Fields," Analysis Report for Task 2 of AP-088, Sandia National Laboratories, Albuquerque, New Mexico (Copy on file in the Sandia WIPP Central Files).

Holt, R. M., and L. Yarbrough, 2003, "Addendum to Estimating Base Transmissivity Fields," Analysis Report for Task 2 of AP-088, Sandia National Laboratories, Albuquerque, New Mexico (Copy on file in the Sandia WIPP Central Files).

Holt, R. M., and L. Yarbrough, 2002, "Estimating Base Transmissivity Fields," Analysis Report for Task 2 of AP-088, Sandia National Laboratories, Albuquerque, New Mexico (Copy on file in the Sandia WIPP Central Files).

Mercer, J. W., D. L. Cole, and R. M. Holt, 1998, "Basic Data Report for Drillholes on the H-19 Hydropad (Waste Isolation Pilot Plant - WIPP)," SAND98-0071, Sandia National Laboratories, Albuquerque, New Mexico.

Holt, R. M., 1997, "Conceptual Model for Transport Processes in the Culebra Dolomite Member, Rustler Formation," SAND97-0194, Sandia National Laboratories, Albuquerque, New Mexico.

Holt, R. M., and D. W. Powers, 1997, "Geologic Controls on Hydraulic Properties in the Rustler Formation, Southeastern New Mexico," Prepared for Westinghouse Electric Corporation, Carlsbad, New Mexico.

Powers, D. W., J. M. Sigda, and R. M. Holt, 1997, "Probability of Intercepting a Pressurized Brine Reservoir Under the WIPP," Prepared for Sandia National Laboratories, Albuquerque, New Mexico.

Holt, R. M., 1996, "Hydrostratigraphy of the Culebra Dolomite Member of the Rustler Formation in the WIPP Region," Records Package WPO#38231, Sandia National Laboratories Albuquerque, New Mexico (Copy on file in the Sandia WIPP Central Files).

Brainard, J. R., P. W. Burck, M. Eliassi, J. T. McCord, R. J. Glass, C. Roepke, R. M. Holt, D. Garret, D. Crowson, D. Fox, P Giarratano, K. Kriel, and M. Mann, 1996, "Tijeras Arroyo Infiltration Experiment," Sandia National Laboratories, Albuquerque, New Mexico.

Powers, D. W., and R. M. Holt, 1995, "Gatuna Formation (Miocene to Pleistocene) Geology and Paleohydrology," Prepared for Westinghouse Electric Corporation, Carlsbad, New Mexico.

Powers, D. W., and R. M. Holt, 1995, "Regional Processes Affecting Rustler Hydrogeology," Prepared for Westinghouse Electric Corporation, Carlsbad, New Mexico.

Roepke, C., R. J. Glass, J. Brainard, M. Mann, K. Kriel, and R. M. Holt, 1995, "Fernald Contaminant Transport Processes Investigation: 1994 Data Report," Prepared for the U. S. Department of Energy Office of Technology Development, Fernald, OH.

Deal, D. E., R. M. Holt, J. M. Melvin, S. M. Djordjevic, 1994, "Calculation of Brine Seepage from Anhydrite Marker Bed 139 into a Waste Storage Room at the Waste Isolation Pilot Plant," DOE-WIPP 94-007, U.S. Department of Energy, WIPP Project Office, Carlsbad, New Mexico.

Holt, R. M., 1993, "Sedimentary Textures, Structures, and Lithofacies in the Salado Formation: A Guide for Recognition, Classification, and Interpretation," DOE-WIPP 92-012 U.S. Department of Energy, WIPP Project Office, Carlsbad, New Mexico.

Holt, R. M., 1993, "Hydrogeology of Markerbed 140 at Boreholes C1H07 and C1X05, Room C1, Waste Isolation Pilot Plant," prepared for Sandia National Laboratories by Holt Hydrogeology.

Holt, R. M., 1993, "Regional Conceptual Hydrogeological Model of the Rustler Formation and Overlying Units, Southeastern New Mexico and West Texas," prepared for Sandia National Laboratories by Holt Hydrogeology.

Crowson, D., J. D. Gibson, C. S. Haase, R. M. Holt, D. Hyndman, 1993, Sandia National Laboratories Site-Wide Hydrogeologic Characterization Project Calendar Year 1992 Annual Report, SAND93-1024, Sandia National Laboratories, Albuquerque, New Mexico.

Holt, R. M., and D. W. Powers, 1990, "Geologic Mapping of the Air Intake Shaft at the Waste Isolation Pilot Plant," DOE-WIPP 90-051, U.S. Department of Energy, WIPP Project Office, Carlsbad, New Mexico.

Holt, R. M., 1990, "An Evaluation of Fracture Data Types, Uses, and Collection Methods from Proposed Underground Excavations at the Yucca Mountain Project (YMP) Site," prepared for Sandia National Laboratories by International Technology Corporation.

Holt, R. M., and D. W. Powers, 1988, "Facies Variability and Post-Depositional Alteration Within the Rustler Formation in the Vicinity of the Waste Isolation Pilot Plant, Southeastern New Mexico," DOE/WIPP-88-004, WIPP Project Office, Carlsbad, New Mexico.

Holt, R. M., and D. W. Powers, 1987, "Rustler Formation in the Waste Handling and Exhaust Shafts, Waste Isolation Pilot Plant (WIPP) Site, Southeastern New Mexico," The Rustler Formation at the WIPP Site: Report of a Workshop on the Geology and Hydrology of the Rustler Formation as it Relates to the WIPP Project, L. Chaturvedi, ed., Environmental Evaluation Group Report EEG-34, pp. 26-35.

Holt, R. M., and D. W. Powers, 1986, "Geotechnical Activities in the Exhaust Shaft," DOE-WIPP-86-008, WIPP Project Office, Carlsbad, New Mexico.

Holt, R. M., and D. W. Powers, 1984, "Geotechnical Activities in the Waste Handling Shaft," WTSD-TME-038, prepared for U.S. Department of Energy by TSC and International Technology Corporation.

Conference Proceedings

Holt, R. M. , J. S. Kuszmaul, Shuang C.C., D. W. Powers, 2013,"Evaluation of Hydraulically Significant Discontinuities in Dockum Group Mudrocks in Andrews County, Texas," Abstract H53A-1409 presented at 2013Fall Meeting, AGU, San Francisco, Calif., 9-15 Dec.

Singh, A., T. Jones, J. Pickens, and R. M. Holt, 2012, "WRVAT: A comprehensive GIS-based water resources vulnerability assessment tool," Gulf Coast Association of Geological Societies Transactions, v. 62, p. 615-618.

Yang, C., K. Romanak, R. M. Holt, J. Lindner, L. Smith, R. Trevino, F. Roecker, Y. Xia, J. Rickerts, S. Hovorka, 2012, "Large Volume of CO2 Injection at the Cranfield, Early Field Test of the SECARB Phase III: Near-Surface Monitoring," Society of Petroleum Engineers - Carbon Management Technology Conference 2012, CMTC 151428, Volume 2, 2012, Pages 746-755.

Blainey, J., J. F. Pickens, G. E. Grisak, R. M. Holt, J. Sigda, S. Cook, and E. Hughes, 2011, "Groundwater Modeling of Playa-Focused Recharge at the Southwestern Edge of the High Plains Aquifer in West Texas," Abstract H53I-1531 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Bowman II, D.O., R.M. Roberts, and R.M. Holt, 2011, "Re-Analysis of Wells Using a Generalized Radial Flow Model," NGWA Focus Conference on Fractured Rock and Eastern Groundwater Regional Issues (#5017) Burlington, Vermont, September 26-27 2011, 15 pp.

Holt, R. M., G. Grisak, E. Hughes, J. Pickens, D. W. Powers, J. S. Kuszmaul, and S. Cook, 2011, "The Hydrogeology of the Upper Dockum Group at the Waste Control Specialists Site, West Texas, USA," 2nd Canadian Symposium on Aquitard Hydrogeology, June 21 - 23, 2011, Ottawa, Canada.

Holt, R. M., G. E. Grisak, E. Hughes, J. F. Pickens, D. W. Powers, J. S. Kuszmaul, and S. Cook, 2011, "The Hydrogeologic Conditions in the Upper Dockum Group at the Waste Control Specialists Site, West Texas," Abstract H53I-1529 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Kuszmaul, J.S., B.J. Gunter, R.M. Holt, T. Jones, T. Holtz, A. Singh, and J. Pickens, 2011, "Development and application of WRVAT to the inventory of dams in Mississippi," in Dam Safety 2010 Conference Proceedings, (Lexington, KY: Association of State Dam Safety Officials), 13 pp.

Kuszmaul, J. S., R. M. Holt, D. W. Powers, R. Beauheim, J. F. Pickens, G. E. Grisak, E. Hughes, and S. Cook, 2011, "Characterization of Hydraulically Significant Discontinuities in Mudrocks at the Waste Control Specialists (WCS) Site, West Texas," Abstract H53I-1530 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Martinez, G. F., A. Singh, R. M. Holt, and G. E. Grisak, 2011, "Unsaturated flow modeling for performance assessment of a radioactive waste disposal facility in Andrews County, Texas," Abstract H53I-1533 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Merrell, G., A. Singh, J. Tauxe, R. Perona, W. Dornsife, G. E. Grisak, and R. M. Holt, 2011, "Performance Assessment of a Low-Level Radioactive Waste Disposal Site using GoldSim Integrated Systems Model," Abstract H53I-1532 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Roecker, F., and R. M. Holt, 2011, "Influence of Capillary Heterogeneity on Leakage of CO2 from a Borehole," Abstract H21C-1120 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Singh, A., R. M. Holt, B. Ramarao, and T. Clemo, 2011, "Simulating Air-Entrapment in Low Permeability Mudrocks using a Macroscopic Invasion Percolation Model," Abstract H54C-08 presented at 2011Fall Meeting, AGU, San Francisco, Calif., 5-9 Dec.

Changbing Yang, Katherine Romanak, Sue Hovorka, Jeff Linder, Rebecca Smyth, Ramon Trevino, Jeff Paine, Bob Holt, L. T. Smith, Yunju Xia, Jiemin Lu, 2010, Geochemical characterization of shallow groundwater at the Cranfield aquifer and numerical simulation: can pH and carbonate parameters be used to detect potential CO2 leakage at geological CO2 sequestration sites? The 9th Annual Conference on Carbon Capture & Sequestration, May 10 - 13, 2010, Pittsburgh, Pennsylvania.

S. Hovorka, D. Freeman, T. Daley, C. Carrigan, D. La Brecque Y. Kharakha, T. Phelps, R. Holt; J. Lindler, and R. Burtch, 2010, "Monitoring a Large Volume Injection, Year Two results - SECARB Project at Denbury's Cranfield, Mississippi, USA, International Conference on Greenhouse Gas Technologies, GHGT10, Amsterdam, The Netherlands, 19th-23rd September 19-23 2010.

Beauheim, R. L., P. S. Domski, R. M. Holt, and D. W. Powers, 2008, "Integration of Thirty Years of Hydrogeological Investigations at the Waste Isolation Pilot Plant Site," EOS Transactions, AGU, Vol. 89, No. 53, Fall Meeting Supplement, Abstract H11H-0870.

Bowman, D. O., R. M. Roberts, and R. M. Holt, 2008, "Parameter Estimation of Transmissivity Fields with Non-Radial Flow Dimensions," EOS Transactions, AGU, Vol. 89, No. 53, Fall Meeting Supplement, Abstract H41A-0828.

Coleman, S. H., D. S. Corely, G. J. Van Volkenburg, J. C. Wildman, and R. M. Holt, 2008, "Conceptual Model for Flow and Transport through Unsaturated Silty Loams and Sands in North Mississippi," EOS Transactions, American Geophysical Union, Joint Assembly Supplement, Vol. 89, No. 23, Abstract H33A-04.

Gunter, B. J., J. S. Kuszmaul, and R. M. Holt, 2008, "Estimating Flooding Potential Associated with Dam Breach Using GIS-Based Modeling," EOS Transactions, AGU, Vol. 89, No. 53, Fall Meeting Supplement, Abstract H11H-0870.

Holt, R. M., E. Hughes, J. M. Hubbell, G. Grisak, S. Cook, J. Pickens, B. C. Griffith, 2008, "A 'Fossil Vadose Zone' from the Triassic Cooper Canyon Formation (Dockum Group) of West Texas," EOS Transactions, AGU, Vol. 89, No. 53, Fall Meeting Supplement, Abstract H51I-0987.

Beauheim, R.L., S.A. McKenna, D.W. Powers, and R.M. Holt, 2007, "Geoscientific Data Collection and Integration for the Waste Isolation Pilot Plant," Linkage of Geoscientific Arguments and Evidence in Supporting the Safety Case, Second AMIGO Workshop Proceedings, Toronto, Canada, 20-22 September 2005, Paris, France: OECD NEA. ISBN 978-92-64-01966-9. p. 125-132.

Holt, R. M., 2007, "Combined Macroscopic Invasion Percolation and Continuum Modeling of Electrical Resistivity Measurements in Unsaturated Media," EOS Transactions, American Geophysical Union, Vol. 88, No. 23, Abstract H41B-03.

Holt, R. M., J. Pickens, T. Jones, J. S. Kuszmaul, P. Phillips, T. Holtz, and B. Gunter, 2007, "A New Vulnerability Assessment Approach for Surface Water and Groundwater," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 88, No. 53, Abstract H33D-1619.

Holtz, T., J. Pickens, T. Jones, R. M. Holt, J. Kuszmaul, B. Gunter, P. Phillips, D. Cobb, D. Caviness, and K. Walters, 2007, "Development of GIS-Based Database and Vulnerability Analysis Tools for Mississippi Groundwater, Surface Water, and Dams," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 88, No. 53, Abstract H13H-1680.

Kuszmaul, J. S., B. Gunter, G. McGregor, R. M. Holt, J. Pickens, T. Holtz, T. Jones, and P. Phillips, 2007, "A Vulnerability Assessment Approach for Dams of Mississippi," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 88, No. 53, Abstract IN23A-0950.

Sigda, J. M., J. L. Wilson, and R. M. Holt, 2007, "Solving Steady Evaporation-Driven Flow Through a Shallow Aquifer With Piecewise Continuous Forms of Hydraulic Relationships," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 88, No. 53, Abstract H21D-0746.

Aufman, M. S., R. M. Holt, and C. J. Hickey, 2006, "Evaluating Electromagnetic Induction Techniques for Predicting Soil Moisture in Loamy Soils," EOS Transactions, American Geophysical Union, Vol. 87, No. 36, Abstract H43A-07.

Holt, R. M., C. J. Hickey, and M. S. Aufman, 2006, "Geophysical Investigations of Soil Moisture in North Mississippi Loams," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 87, No. 52, Abstract H11F-1321.

Holt, R. M., C. J. Hickey, and M. S. Aufman, 2006, "Geophysical Investigations of Soil Moisture at the University of Mississippi Soil Moisture Observatory," ASA-CSSA-SSSA 2006 International Meetings, Abstract No. 178-23.

Bowman, D. O., R. M. Roberts, and R. M. Holt, 2006, "Generation of Transmissivity Fields with Non-radial Flow Dimensions," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 87, No. 52, Abstract H13D-1428.

Hossain, A. A., G. Easson, D. W. Powers, and R. M. Holt, 2006, "Developing Methods for Mapping Soil Moisture in Nash Draw, NM Using RADARSAT 1 SAR Fine Imagery," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 87, No. 52, Abstract H31D-1457.

Johnson, E. G., and R. M. Holt, 2006, "Simulation of Groundwater Age Distributions Using Radioactive Solutes in Double-Porosity Media," EOS Transactions, American Geophysical Union, Fall Meeting Supplement, Vol. 87, No. 52, Abstract H43C-0510.

Bowman, D.O., R. M. Holt, and R. M. Roberts, 2005, "Flow Dimension Analysis of Pumping Tests for use in Hydraulic Tomography," EOS Transactions, Fall Meeting Supplement, American Geophysical Union, Vol. 86., No. 52, Abstract H51A-0346.

Holt, R. M., R. M Roberts, and D. O. Bowman, 2005, "Generalized Radial Transport for Tracer Tests in Fractured Rock," EOS Transactions, Fall Meeting Supplement, American Geophysical Union, Vol. 86., No. 52, Abstract H51A-0338.

Aufman, M. S., and R. M. Holt, 2005, "Spatial and Temporal Variations in Electrical Conductivity in North Mississippi Loamy Soils," Abstract, EOS Transactions, American Geophysical Union, Vol. 86, No. 18, p. JA132.

Bowman, D. O., R. M. Holt, and R. M. Roberts, 2005, "Flow Dimension Analysis of Pumping Tests in Indicator Fields," Abstract, EOS Transactions, American Geophysical Union, Vol. 86, No. 18, p. JA 175.

Holt, R. M., K. E. Baker, and A. L. Schafer, 2005, "Influence of the Air-Entry Pressure Ratio in Bimodal Heterogeneous Unsaturated Zones," Abstract, EOS Transactions, American Geophysical Union, Vol. 86, No. 18, p. JA133-JA134.

Katsube, T. J., H. McNairn, Y. Das, E. Gauthier, R. M. Holt, V. Singhroy, R. DiLabio, S. Connell-Madore, and L. Dyke, 2005, "Rapid mapping of soil electrical conductivity by remote sensing: implication for landmine detection and vehicle mobility," in R. S. Harmon, J. T. Broach, and J. H. Holloway, Jr., eds., Detection and Remediation Technologies for Mines and Minelike Targets X, Proceedings of the SPIE, Vol. 5794, p. 144-156.

McNairn, H., T. J. Katsube, Y. Das, and R. M. Holt, 2005, "Rapid Mapping of Soil Electrical Conductivity by Radar Satellite Remote Sensing for Landmine Detection," Abstract, EOS Transactions, American Geophysical Union, Vol. 86, No. 18, p. JA161.

Beauheim, R. L., D. W. Powers, and R. M. Holt, 2004, "Predicting Fractured Zones in the Culebra Dolomite," Proceedings of the Second International Symposium on Dynamics of Fluids in Fractured Rock., LBNL-54275, Berkeley, CA: Ernest Orlando Lawrence Berkeley National Laboratory, pp. 400-406.

Bowman, D. O., R. M. Holt, and R. M. Roberts, 2004, "Flow Dimension Analysis of Pumping Tests in Geometric and Random Fields," Abstract, EOS Transactions, American Geophysical Union, Vol. 85, No. 47, Abstract No. H33F-0532, p. F829.

Cheng, A., G. Davidson, and R. M. Holt, 2004, "Yazoo River Basin (Lower Mississippi River) Hydrologic Observatory," Abstract, EOS Transactions, American Geophysical Union, Vol. 85, No. 47, Abstract No. H31C-0388, p. F797.

Griffith, B. C., R. M. Holt, K. Baker, T. McLing, and A. Schafer, 2004, "Defining the Spatial Structure of Sedimentary Interbeds within Basalt at the Vadose Zone Research Park," Abstract, EOS Transactions, American Geophysical Union, Vol. 85, No. 47, Abstract No. H11B-0303, p. F699.

Holland, J. V., C. W. Fancher, M. D. Sleep, J. E. Twombly, M. S. Aufman, R. M. Holt, and J. S. Kuszmaul, 2004, "Spatial Variations in Soil Properties at the University of Mississippi Soil Moisture Observatory," EOS Transactions, Vol. 85, No. 17, Joint Assembly Supplement, Abstract H23C-03.

Sleep, M. D., R. M. Holt, and J. S. Kuszmaul, 2004, "Spatial Variability of Electerical Conductivity and Its Relationship to Soil Properties at The University of Mississippi Soil Moisture Observatory," Abstract, EOS Transactions, American Geophysical Union, Vol. 85, No. 47, Abstract No. H33E-0514, p. F826.

Twombly, J. E., C. W. Fancher, M. D. Sleep, M. S. Aufman, J. V. Holland, R. M. Holt, and J. S. Kuszmaul, 2004, Spatial Variability of Electrical Conductivity in North Mississippi Loamy Soils, EOS Transactions, Vol. 85, No. 17, Joint Assembly Supplement, Abstract H23C-02.

Griffith, B. C., R. M. Holt, and R. J. Glass, 2003, "Generating Reproducible Heterogeneity for Laboratory Flow and Transport Experiments," Abstract, EOS Transactions, American Geophysical Union, Vol. 84, No. 46, p. Abstract No. H32A-0529.

Holt, R. M., 2003, "Hydrologic Heterogeneity: Failure of the Geostatistical Approach," Geological Society of America Abstracts, Vol. 34, No. 7, p. 124. (Invited Presentation)

Holt, R. M., R. J. Glass, J. M. Sigda, and E. D. Mattson, 2003, "Phase Structure in a Centrifugal Field: Impact of Capillary Heterogeneity and Angular Velocity," Abstract, EOS Transactions, American Geophysical Union, Vol. 84, No. 46, Abstract No. H22A-0909.

Johnson, E. G., R. M. Holt, and T. L. McLing, 2003, "A Geologically-Based Approach for Determining Distributions of Mass Transfer Coefficients in Fractured Rock Systems," Geological Society of America Abstracts, Vol. 34, No. 7, p. 411.

Holt, R. M., and E. D. Mattson, 2002, "Influence of Wetted-Phase Structure on the Electrical Conductivity-Moisture Content Relationship," Abstract, EOS Transactions, American Geophysical Union, Vol. 83, No. 47, p. F575.

Holt, R. M., and D. W. Powers, 2002, "Impact of Salt Dissolution on the Transmissivity of the Culebra Dolomite Member of the Rustler Formation, Delaware Basin, Southeastern New Mexico," Abstracts with Programs, Geological Society of America, v. 34, no. 6, p. 215.

Johnson, E. G., R. M. Holt, and T. L. McLing, 2002, "Diffusion as a Rate Limiting Factor on the Evolution of Strontium Isotope Ratios in Fractured Rock," Abstract, EOS Transactions, American Geophysical Union, Vol. 82, No. 47, p. F489.

Holt, R. M., 2001, "Spatial Bias in Unsaturated Hydraulic Property Estimates: Origin, Impact, and Relevance," Abstract, Presentation Abstracts, Eighth Biannual Unsaturated Zone Interest Group Meeting, July 30 through August 2, 2001, Idaho Falls, Idaho, sponsored by the U. S. Geological Survey, U.S. Dept. of Energy, and Idaho National Engineering and Environmental Laboratory, p. 24.

Holt, R. M., 2001, "Impact of Hydraulic Property Measurement Errors on Geostatistical Characterization and Stochastic Flow and Transport Modeling," Abstract, EOS Transactions, American Geophysical Union, Vol. 82, No. 47, p. F576.

Holt, R. M., and A. L. Schafer, 2001, "Indicator Variograms Estimated from Spatially-Biased Field Data," Geological Society of America Abstracts, Vol. 33, No. 6, p. A-135.

Johnson, E. G., T. L. McLing, and R. M. Holt, 2001, "Conceptual Hydrogeologic Models for the Eastern Snake River Plain, Idaho," Abstract, EOS Transactions, American Geophysical Union, Vol. 82, No. 47, p. F489.

Powers, D. W., R. M. Holt, and E. L. Powers, 2001, "Recycling Sequestered Bacteria Through Natural Hydrogeologic Processes," Abstract, EOS Transactions, American Geophysical Union, Vol. 82, No. 47, p. F179.

Schafer, A. L., and R. M. Holt, 2001, "Modeling Unsaturated Flow and Transport using Zones: Aliasing Errors," Abstract, EOS Transactions, American Geophysical Union, Vol. 82, No. 47, p. F375.

Yarbrough, L., G. Easson, and R.M. Holt, 2001, "Geologic and Hydrologic Analysis with Geographic Information Systems," Abstract, AEG News, Vol. 44, No. 4, p. 80.

Baker, K. E., R. M. Holt, and R. J. Glass, 2000, "Can Pedotransfer Function Models be used to Characterize Unsaturated Hydraulic Properties in Geologic Materials," Abstract, Twelfth TIE Workshop Book, U.S. Department of Energy, p. 146.

Holt, R. M., J. L. Wilson, and R. J. Glass, 2000, "Error in Unsaturated Stochastic-Models Parameterized with Field Data," Abstract, EOS Transactions, American Geophysical Union, Vol. 81, No. 48, p. F408

Holt, R. M., 2000, "Can We Parameterize Stochastic Models of Flow and Transport in the Vadose Zone," Abstract, Twelfth TIE Workshop Book, U.S. Department of Energy, p. 165.

Holt, R. M., J. L. Wilson, and R. J. Glass, 1999, "Spatial Bias in Unsaturated Hydraulic Properties due to Laboratory Error," Abstract, EOS Transactions, American Geophysical Union, Vol. 80, No. 46, pp. F389-390

Holt, R. M., J. L. Wilson, and R. J. Glass, 1998, "Estimating Variogram-Model Parameters for Hydraulic Properties in the Presence of Measurement Error: Example from the Tension Infiltrometer," Abstract, EOS Transactions, American Geophysical Union, Vol. 79, No. 45, p. F267

Holt, R. M., 1997, "Geologically-Based Estimates of Multiple-Rate Transport Parameters for the Culebra Dolomite," Abstract, EOS Transactions, American Geophysical Union, Vol. 78, No. 46, p. F331.

Holt, R. M., 1996, "Using Geologic Information to Develop Conceptual Models for Reactive Contaminant Transport in Fractured Media: An Example from the Culebra Dolomite Member of the Rustler Formation," Abstract, EOS Transactions, American Geophysical Union, Vol. 77, No. 46, p. F225.

Swift, D. J. P., B. Parsons, A. Muller, J. L. Wilson, R. G. Taylor, R. M. Holt, R. Smith, A. Schaffer, and T. McLing, 1996, "Sedimentary Facies as a Guide to Hydrologic Properties in an Experimental Aquifer of Shallow Marine Origin: Virginia's Eastern Shore Peninsula," Abstract, EOS Transactions, American Geophysical Union, Vol. 77, No. 17, p. S100.

Holt, R. M., J. L. Wilson, and R. J. Glass, 1995, "Approximate Solution of Steady Unsaturated Flow Equations using a Piecewise Hydraulic Conductivity Function," Abstract, EOS Transactions, American Geophysical Union, Vol. 76, No. 46, p. F262.

Roepke, C., R. J. Glass, J. Brainard, M. Mann, K. Kriel, R. M. Holt, and J. Schwing, 1995, "The Transport Processes Investigation: A Necessary First Step in Site Characterization Plans," Proceedings of Waste Management Symposia 1995, Tucson, AZ.

Holt, R. M., and E. K. Webb, 1994, "The Conceptual Hydrogeological Modeling Process: Incorporating Sedimentary and Stratigraphic Data," Geological Society of America Abstracts, Vol. 26, No. 7, p. A-416.

Crowson, D., J. T. McCord, R. Holt, J. Piper, and E. K. Webb, 1993, "Detailed Mapping and Preliminary Geostatistical Analysis of Alluvial Fan Deposits Exposed in Six Miles of Trench," Abstract, 1993 Spring Meeting Supplement to EOS Transactions, April 20, 1993, American Geophysical Union, p. 143.

Holt, R. M., and D. W. Powers, 1991, "Water Table Controlled Syndepositional Alteration Textures and Fabrics in Salt Pan Halite: Modern Analogues and Ancient Examples," Abstract, Proceedings of the American Association of Petroleum Geologists/Society for Sedimentary Geology Annual Meeting, Dallas, Texas.

Holt, R. M., and R. L. Beauheim, 1990, "Depositional and Diagenetic controls on Transmissivity Variations in the Culebra Dolomite Near the WIPP Site," Abstract, EOS Transactions, American Geophysical Union, Vol. 71, No. 17, p. 511.

Holt, R. M., D. W. Powers, R. L. Beauheim, and M. E. Crawley, 1988, "Origin of Transmissivity Variations in the Culebra Dolomite Near the Waste Isolation Pilot Plant Site, Southeastern New Mexico," Abstract, Groundwater Journal, Vol. 26, No. 6, p. 790.

Powers, D. W., M. Martin, and R. M. Holt, 1988, "Silici-clastic-rich Units of the Permian Salado Formation, Southeastern New Mexico," Geological Society of America Abstracts, Vol. 20, No. 7, p. A174.

Holt, R. M., and D. W. Powers, 1986, "Rustler Formation: Evaporite End Stages of a Continental Basin," Abstract, 12th Int. Sed. Cong., pp. 141-142.

Powers, D. W., and R. M. Holt, 1984, "Depositional Environments and Dissolution in the Rustler Formation (Permian), Southeastern New Mexico," Abstract, 97th Annual Meeting, Geological Society of America, p. 627

Edited Volumes/Special Issues of Journals

Holt, R. M., and M. Nicholl, eds., 2004, "Special Section: Uncertainty in Vadose Zone Flow and Transport Properties," Vadose Zone Journal, Vol. 3, No. 2. Includes 9 peer-reviewed manuscripts.

Powers, D. W., R. M. Holt, R. L. Beauheim, and N. Rempe, eds., 1990, "Geological and Hydrological Studies of Evaporites in the Northern Delaware Basin for the Waste Isolation Pilot Plant (WIPP)," Geological Society of America Fieldtrip Guidebook 14, 186 pp. Includes 9 peer-reviewed manuscripts.