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Rheannon M Hart
I am a hydrologist for the U.S. Geological Survey Arkansas Water Science Center and hold a Bachelor of Science and a Master of Science in Geology from the University of Arkansas at Little Rock. Since joining the USGS in 2001, I have been involved in collecting water levels and creating potentiometric surfaces for several aquifers within the State; characterizing the local recharge area of a spring that is habitat to the endangered Hell Creek Cave crayfish; developing the hydrogeologic framework for the Mississippi embayment aquifer system for use in the Mississippi Embayment Regional Aquifer Study (MERAS) groundwater flow model; developing a Hydrologic Simulation Program--FORTRAN (HSPF) model of Little Rock's drinking water supply watershed; developing a HSPF model of Conway's drinking water supply watershed; developing a PRMS model of the entire Landscape Conservation Cooperative Gulf Coastal Plains and Ozarks area simulating daily streamflow; developing dynamic parameters for land use and land cover data extending back to 1938 to aid in the development of the National Hydrologic Model; and developing a PRMS model, loosely coupled to a MODFLOW model, to determine the extent of the recharge area of the hot springs of the Hot Springs National Park. I also currently run the geophysical logging program within the center using our own geophysical logging truck and geophysical tools.
Science and Products
Trace-metal and organic constituent concentrations in bed sediment at Big Base and Little Base Lakes, Little Rock Air Force Base, Arkansas—Comparisons to sediment-quality guidelines and indications for timing of exposure
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.
Lithology, hydrologic characteristics, and water quality of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas
A study to assess the potential of the Arkansas River Valley alluvial aquifer in the vicinity of Van Buren, Arkansas, as a viable source of public-supply water was conducted by the U.S. Geological Survey in cooperation with the Little Rock, District, U.S. Army Corps of Engineers. An important study component was to identify possible changes in...Kresse, Timothy M.; Westerman, Drew A.; Hart, Rheannon M.
Simulated effects of existing and proposed surface-water impoundments and gas-well pads on streamflow and suspended sediment in the Cypress Creek watershed, Arkansas
Cypress Creek is located in central Arkansas and is the main tributary to Brewer Lake, which serves as the primary water supply for Conway, Arkansas, and the surrounding areas. A model of the Cypress Creek watershed was developed and calibrated in cooperation with Southwestern Energy Company using detailed precipitation, streamflow, and discrete...Hart, Rheannon M.
Simulated effects of hydrologic, water quality, and land-use changes of the Lake Maumelle watershed, Arkansas, 2004–10
Lake Maumelle, located in central Arkansas northwest of the cities of Little Rock and North Little Rock, is one of two principal drinking-water supplies for the Little Rock, and North Little Rock, Arkansas, metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other reservoirs and streams in...Hart, Rheannon M.; Green, W. Reed; Westerman, Drew A.; Petersen, James C.; DeLanois, Jeanne L.
Groundwater availability of the Mississippi embayment
Groundwater is an important resource for agricultural and municipal uses in the Mississippi embayment. Arkansas ranks first in the Nation for rice and third for cotton production, with both crops dependent on groundwater as a major source of irrigation requirements. Multiple municipalities rely on the groundwater resources to provide water for...Clark, Brian R.; Hart, Rheannon M.; Gurdak, Jason J.
Effects of Simulated Land-Use Changes on Water Quality of Lake Maumelle, Arkansas
Lake Maumelle is one of two principal drinking-water supplies for the Little Rock and North Little Rock metropolitan areas. Lake Maumelle and the Maumelle River (its primary tributary) are more pristine than most other reservoirs and streams in the region. However, as the Lake Maumelle watershed becomes increasingly more urbanized and timber...Hart, Rheannon M.; Westerman, Drew A.; Petersen, James C.; Green, W. Reed; De Lanois, Jeanne L.
Assessment of Local Recharge Area Characteristics of Four Caves in Northern Arkansas and Northeastern Oklahoma, 2004-07
A study was conducted from 2004 to 2007 by the U.S. Geological Survey in cooperation with the U.S. Fish and Wildlife Service to assess the characteristics of the local recharge areas of four caves in northern Arkansas and northeastern Oklahoma that provide habitat for a number of unique organisms. Characterization of the local recharge areas are...Gillip, Jonathan A.; Galloway, Joel M.; Hart, Rheannon M.
The Mississippi Embayment Regional Aquifer Study (MERAS): Documentation of a Groundwater-Flow Model Constructed to Assess Water Availability in the Mississippi Embayment
The Mississippi Embayment Regional Aquifer Study (MERAS) was conducted with support from the Groundwater Resources Program of the U.S. Geological Survey Office of Groundwater. This report documents the construction and calibration of a finite-difference groundwater model for use as a tool to quantify groundwater availability within the Mississippi...Clark, Brian R.; Hart, Rheannon M.
Geophysical Log Database for the Mississippi Embayment Regional Aquifer Study (MERAS)
The Mississippi Embayment Regional Aquifer Study (MERAS) is an investigation of ground-water availability and sustainability within the Mississippi embayment as part of the U.S. Geological Survey Ground-Water Resources Program. The MERAS area consists of approximately 70,000 square miles and encompasses parts of eight states including Alabama,...Hart, Rheannon M.; Clark, Brian R.
Digital Surfaces and Thicknesses of Selected Hydrogeologic Units within the Mississippi Embayment Regional Aquifer Study (MERAS)
Digital surfaces of selected Tertiary and younger age hydrogeologic units within the Mississippi embayment aquifer system were created using more than 2,600 geophysical logs for an area that covers approximately 70,000 square miles and encompasses parts of eight states. The digital surfaces were developed to define and display the hydrogeologic...Hart, Rheannon M.; Clark, Brian R.; Bolyard, Susan E.
Monitoring the Recovery of the Sparta Aquifer in Southern Arkansas and Northern Louisiana
The Sparta aquifer supplies the majority of water for industrial, municipal, and agricultural uses in Union County, Arkansas, and the surrounding area. In Union County, the Sparta aquifer has been used increasingly since development began in the early 1920s, resulting in water-level declines of more than 360 feet (ft) in some areas. In addition,...Scheiderer, Rheannon M.; Freiwald, David A.
Status of water levels in aquifers in the Nacatoch Sand of southwestern and northeastern Arkansas and the Tokio Formation of southwestern Arkansas, 2002
Aquifers in the Nacatoch Sand and Tokio Formation in southwestern Arkansas and the Nacatoch Sand in northeastern Arkansas are sources of water for industrial, public supply, domestic, and agricultural uses. Potentiometric-surface maps were constructed from water-level measurements made in 60 wells completed in the Nacatoch Sand and 48 wells...Schrader, Tony P.; Scheiderer, Rheannon M.