Short Title: North Ground-Water Model
Project Chief: Phillip Hays
Cooperators: Arkansas Natural Resources Commission
Project Time Frame: 2005 - present
Several counties in eastern and southern Arkansas have been designated Critical Ground-Water Areas (areas where alluvial aquifer...
Short Title: Ozark Karst Study
Project Chiefs: Tim Kresse (USGS-Water), Phil Hays (USGS-Water), James Kaufmann (USGS-Geography), Mark Hudson (USGS-Geology), Esther Stroh (USGS-Biology)
Cooperator: U.S. Geological Survey
Project Time Frame: 2007 - 2011
Three major physiographic provinces in the Ozark Plateaus in Arkansas and Missouri include diverse topography and...
Short Title: Hot Springs Thermal Study
Project Chief: Tim Kresse
Cooperators: Arkansas State Highway and Transportation Department
Project Time Frame: 2007 - 2009
Established in 1832 to preserve 47 hot springs flowing from of Hot Springs Mountain, Hot Springs National Park (HSNP) is the oldest National Park in the...
A three-dimensional hydrogeologic framework of the Hot Springs anticlinorium beneath Hot Springs National Park, Arkansas, was constructed to represent the complex hydrogeology of the park and surrounding areas to depths exceeding 9,000 feet below ground surface. The framework, composed of 6 rock formations and 1 vertical fault emplaced beneath the...
Hart, Rheannon M.; Ikard, Scott J.; Hays, Phillip D.; Clark, Brian R.
The Phosphorus (P) Index risk assessment tool has been widely adopted across the U.S. to identify and rank site vulnerability to P runoff as part of the Natural Resources Conservation Service (NRCS) nutrient management planning (NMP) process. However, limited success has been achieved in addressing the risk of P loss by subsurface flow pathways,...
Sharpley, Andrew N.; Hays, Phillip D.; Daniels, Michael B.; VanDevender, Karl W.
The Ouachita Mountains aquifer system potentiometric-surface map is one component of the Hot Springs Bypass Groundwater Monitoring Project. The potentiometric-surface map provides a baseline assessment of shallow groundwater levels and flow directions before the construction of the Arkansas Department of Transportation planned extension of the...
Nottmeier, Anna M.; Hays, Phillip D. For many people, a visit to a cave is a wondrous event directing our minds to ponder the mysteries presented by these unique places and inspiring questions: How old is the cave? What was the role of water in forming the cave and where did the water come from? How is the cave connected to the surface environment? These are intriguing questions to...
Knierim, Katherine J.; Hays, Phillip D. Instream biogeochemical process measurements are often short-term and localized. Here we use in situ sensors to quantify the net effects of biogeochemical processes on seasonal patterns in baseflow nitrate retention at the river-reach scale. Dual-station high-frequency in situ nitrate measurements, were coupled with high-frequency measurements of...
Jarvie, Helen P.; Sharpley, Andrew N.; Kresse, Timothy M.; Hays, Phillip D.; Williams, Richard J.; King, Stephen M.; Berry, Lawrence G. The nature of carbon (C) cycling in the unsaturated zone where groundwater is in contact with abundant gas-filled voids is poorly understood. The objective of this study was to trace inorganic-C cycling in a karst landscape using stable-C isotopes, with emphasis on a shallow groundwater flow path through the soil, to an underlying cave, and to the...
Knierim, Katherine J.; Pollock, Erik D.; Covington, Matthew D.; Hays, Phillip D.; Brye, Kristofor R.
The hydrogeology and hydrologic characteristics of the Ozark Plateaus aquifer system were characterized as part of ongoing U.S. Geological Survey efforts to assess groundwater availability across the Nation. The need for such a study in the Ozark Plateaus physiographic province (Ozark Plateaus) is highlighted by increasing demand on groundwater...
Hays, Phillip D.; Knierim, Katherine J.; Breaker, Brian K.; Westerman, Drew A.; Clark, Brian R.
A hydrogeologic framework was constructed to represent the altitudes and thicknesses of hydrogeologic units within the Ozark Plateaus aquifer system as part of a regional groundwater-flow model supported by the U.S. Geological Survey Water Availability and Use Science Program. The Ozark Plateaus aquifer system study area is nearly 70,000 square...
Westerman, Drew A.; Gillip, Jonathan A.; Richards, Joseph M.; Hays, Phillip D.; Clark, Brian R.
This report compares concentrations for a wide range of inorganic and organic constituents in bed sediment from Big Base Lake and Little Base Lake, which are located on Little Rock Air Force Base, Arkansas, to sediment-quality guidelines. This report also compares trace-metal concentrations in a bed-sediment core sample to sediment age to...
Justus, B.G.; Hays, Phillip D.; Hart, Rheannon M. Stable-isotope analyses are valuable in karst settings, where characterizing biogeochemical cycling of carbon along groundwater flow paths is critical for understanding and protecting sensitive cave and karst water resources. This study quantified the seasonal changes in concentration and isotopic composition (δ13C) of aqueous and gaseous...
Knierim, Katherine J.; Pollock, Erik; Hays, Phillip D.; Khojasteh, Jam
Sixteen aquifers in Arkansas that currently serve or have served as sources of water supply are described with respect to existing groundwater protection and management programs, geology, hydrologic characteristics, water use, water levels, deductive analysis, projections of hydrologic conditions, and water quality. State and Federal protection...
Kresse, Timothy M.; Hays, Phillip D.; Merriman, Katherine R.; Gillip, Jonathan A.; Fugitt, D. Todd; Spellman, Jane L.; Nottmeier, Anna M.; Westerman, Drew A.; Blackstock, Joshua M.; Battreal, James L. Exploration of unconventional natural gas reservoirs such as impermeable shale basins through the use of horizontal drilling and hydraulic fracturing has changed the energy landscape in the USA providing a vast new energy source. The accelerated production of natural gas has triggered a debate concerning the safety and possible environmental...
Warner, Nathaniel R.; Kresse, Timothy M.; Hays, Phillip D.; Down, Adrian; Karr, Jonathan D.; Jackson, R.B.; Vengosh, Avner