Gregory Cherry
Biography
Education California State University at Chico Bachelor of Science, Geology, 1986
Professional Work Experience United States Geological Survey, Atlanta, Georgia South Atlantic Water Science Center, Norcross Office Hydrologist, GS-1315-12, 2002-Present
Currently serving as Project Chief for the Brunswick/Glynn County Cooperative Water Program, which monitors saltwater contamination in the Upper Floridan aquifer. The project combines groundwater modeling with annual water-quality sampling to assess saltwater movement near the City of Brunswick. Model development has involved using a regional model and refining into a smaller grid configuration near the area of interest. The modeling work has used optimization techniques (GWM code) to maximize pumping near active production wells while preserving hydraulic head gradients and the mitigate movement of the chloride plume. Provides monthly progress reports for the Water Resource Management Advisory Committee (WRMAC) at meetings held in Brunswick. The WRMAC consists of representatives from local government agencies, industrial facilities, and concerned citizens. Previously, data collected annually was submitted to the WRMAC in a written report, but data is now published as a USGS open-file report and made available on the USGS website. Data and significant findings have been presented at conferences, symposia, and local outreach events.
Project Chief on several small modeling projects in which existing models were used to evaluate increases in pumping and determine effects on the local aquifers. One of these projects used the groundwater model constructed for the Savannah River Site (SRS) and evaluated potential increases in pumping at the Plant Vogtle Electrical Generating Facility. The other project used a regional groundwater model of coastal Georgia and parts of South Carolina and Florida to determine changes in the Upper Floridan aquifer caused by increased pumping at U.S. Army Fort Stewart and Hunter Army Airfield. The work for the U.S. Army had very tight schedules and required concurrent reviews to meet project deadlines. Similar studies have been performed for the cities of Pooler, Rincon, and Berwick located in Chatham County, Georgia.
Georgia Association of Water Professionals--Member Georgia Ground Water Association--Vice Chairman 2005 to Present
Science and Products
Groundwater Modelling of the Edisto River Basin, South Carolina
The USGS SAWSC in cooperation with the South Carolina Department of Natural Resources (SCDNR) will use an existing, published groundwater-flow model of the South Carolina Coastal Plain aquifers and confining units to simulate current groundwater conditions and future water-use scenarios developed by SCDNR. The published groundwater-flow model was constructed using existing hydrogeologic and...
Groundwater Monitoring Program for the Brunswick-Glynn County Area, Georgia
In the Brunswick, Georgia area, saltwater has contaminated the Upper Floridan aquifer for nearly 50 years. Saltwater contamination has constrained further development of the Upper Floridan aquifer in the Brunswick area, which has stimulated interest in the development of alternative sources of water supply, primarily from the shallower surficial and Brunswick aquifer systems.
USGS is...
Simulation of groundwater flow in the Brunswick Area, Georgia, for 2004 and 2015, and selected groundwater-management scenarios
The Upper Floridan aquifer (UFA) is the principal water source for industrial and public supply in Glynn County, Georgia. Wells in active pumping centers that tap the UFA for industries near the city of Brunswick have created an upward hydraulic-head gradient in the Floridan aquifer system, which has allowed high chloride (saline) groundwater from...
Cherry, Gregory S.
Simulated effects of Lower Floridan aquifer pumping on the Upper Floridan aquifer at Barbour Pointe, Chatham County, Georgia
Steady-state simulations using a revised regional groundwater-flow model based on MODFLOW were run to assess the potential long-term effects on the Upper Floridan aquifer (UFA) of pumping the Lower Floridan aquifer (LFA) at well 36Q398, located at Barbour Pointe in coastal Georgia near Savannah. Simulated pumping of well 36Q398 at a rate of 750...
Cherry, Gregory S.; Clarke, John S.
Saltwater intrusion in the Floridan aquifer system near downtown Brunswick, Georgia, 1957–2015
IntroductionThe Floridan aquifer system (FAS) consists of the Upper Floridan aquifer (UFA), an intervening confining unit of highly variable properties, and the Lower Floridan aquifer (LFA). The UFA and LFA are primarily composed of Paleocene- to Oligocene-age carbonate rocks that include, locally, Upper Cretaceous rocks. The FAS extends from...
Cherry, Gregory S.; Peck, Michael
Groundwater flow in the Brunswick/Glynn County area, Georgia, 2000-04
An existing regional steady-state model for coastal Georgia, and parts of South Carolina and Florida, was revised to evaluate the local effects of pumping on the migration of high chloride (saline) water in the Upper Floridan aquifer located in the Brunswick/Glynn County, Georgia (Ga.) area. Revisions were focused on enhancing the horizontal and...
Cherry, Gregory S.
Simulated effects of Lower Floridan aquifer pumping on the Upper Floridan aquifer at Rincon, Effingham County, Georgia
Steady-state simulations using a revised regional groundwater-flow model based on MODFLOW were run to assess the potential long-term effects on the Upper Floridan aquifer (UFA) of pumping the Lower Floridan aquifer (LFA) at well (36S048) near the City of Rincon in coastal Georgia near Savannah. Simulated pumping of well 36S048 at a rate of 1,000...
Cherry, Gregory S.; Clarke, John S.
Simulated effects of Lower Floridan aquifer pumping on the Upper Floridan aquifer at Pooler, Chatham County, Georgia
A revised regional groundwater-flow model was used to assess the potential effects on the Upper Floridan aquifer (UFA) of pumping the Lower Floridan aquifer (LFA) from a new well (35Q069) located at the City of Pooler in coastal Georgia near Savannah. The spatial resolution of the original regional, steady-state, groundwater-flow model was...
Cherry, Gregory S.; Clarke, John S.
Groundwater conditions in the Brunswick-Glynn County area, Georgia, 2009
The Upper Floridan aquifer is contaminated with saltwater in a 2-square-mile area of downtown Brunswick, Georgia. The presence of this saltwater has limited the development of the groundwater supply in the Glynn County area. Hydrologic, geologic, and water-quality data are needed to effectively manage water resources. Since 1959, the U.S....
Cherry, Gregory S.; Peck, Michael F.; Painter, Jaime A.; Stayton, Welby L.
Groundwater modeling to evaluate interaquifer leakage in the Floridan aquifer system near Hunter Army Airfield and Fort Stewart
Simulations using a modified regional groundwater- flow model were used to determine the amount of leakage from the Upper Floridan aquifer (UFA) through the Lower Floridan confining unit (LFC) into the Lower Floridan aquifer (LFA) resulting from pumping about 1 million gallons per day at newly constructed LFA production wells at Hunter Army...
Cherry, Gregory S.
Groundwater conditions and studies in the Brunswick–Glynn County area, Georgia, 2008
The Upper Floridan aquifer is contaminated with saltwater in a 2-square-mile area of downtown Brunswick, Georgia. This contamination has limited development of the groundwater supply in the Glynn County area. Hydrologic, geologic, and water-quality data are needed to effectively manage water resources. Since 1959, the U.S. Geological Survey has...
Cherry, Gregory S.; Peck, Michael F.; Painter, Jaime A.; Stayton, Welby L.
Ground-Water Conditions and Studies in the Brunswick-Glynn County Area, Georgia, 2007
The Upper Floridan aquifer is contaminated with saltwater in a 2-square-mile area of downtown Brunswick, Georgia. This contamination has limited the development of the ground-water supply in the Glynn County area. Hydrologic, geologic, and water-quality data are needed to effectively manage water resources. Since 1959, the U.S. Geological Survey...
Cherry, Gregory S.; Clarke, John S. Simulation and Particle-Tracking Analysis of Selected Ground-Water Pumping Scenarios at Vogtle Electric Generation Plant, Burke County, Georgia
The source of ground water to production wells at Vogtle Electric Generation Plant (VEGP), a nuclear power plant in Burke County, Georgia, was simulated under existing (2002) and potential future pumping conditions using an existing U.S. Geological Survey (USGS) MODFLOW ground-water flow model of a 4,455-square-mile area in the Coastal Plain of...
Cherry, Gregory S.; Clarke, John S. U.S. Geological Survey Georgia Water Science Center and City of Brunswick- Glynn County Cooperative Water Program-Summary of Activities, July 2005 through June 2006
Since 1959, the U.S. Geological Survey has conducted a cooperative water resources program (CWP) with the City of Brunswick and Glynn County in the Brunswick, Georgia, area. Since the late 1950s, the salinity of ground water in the Upper Floridan aquifer near downtown Brunswick, Georgia, has been increasing, and its occurrence has been detected...
Cherry, Gregory S.