Deborah Repert
Deb Repert is a Microbiologist for the USGS Water Resources Mission Area.
Deb Repert has worked with the USGS since 1998 as a microbiologist focusing on nitrogen cycling processes in aquatic environments. She is interested in the physical, chemical and microbiological processes controlling the transport and fate of nutrients in both pristine and contaminated environments.
She received an undergraduate degree in Biology from Clarkson University and a Master's degree in Zoology with an emphasis in microbiology and stream ecology from Michigan State University.
Education
M.S. - Zoology, emphasis in microbiology and stream ecology, Michigan State University, 1992
B.S. - Biology, Clarkson University, 1988
Employment
Microbiologist, National Research Program, US Geological Survey, Boulder, CO, 1998-present
Research Technician, The Louis Calder Center, Fordham University, Armonk, NY, 1993-1997
Stream Research Coordinator, Arctic LTER Project, The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA ,1992-1993
Laboratory Technician, Clarkson University, Potsdam, NY, 1988-1989
Science and Products
Filter Total Items: 15
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inor
Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inor
Water and Sediment Geochemistry Data from the Vicinity of Yellow Pine, Idaho, 2014-2015
Samples were collected at or near baseflow conditions. Water pH and specific conductance were measured in the field, with specific conductance also measured in the laboratory and calculated based on the ionic strength of samples based on laboratory analyses. Water samples were collected for laboratory analyses using a peristaltic pump with silicon tubing. Samples were filtered through a reusabl
Filter Total Items: 22
Long-term groundwater contamination after source removal—The role of sorbed carbon and nitrogen on the rate of reoxygenation of a treated-wastewater plume on Cape Cod, MA, USA
The consequences of groundwater contamination can remain long after a contaminant source has been removed. Documentation of natural aquifer recoveries and empirical tools to predict recovery time frames and associated geochemical changes are generally lacking. This study characterized the long-term natural attenuation of a groundwater contaminant plume in a sand and gravel aquifer on Cape Cod, Mas
Authors
Richard L. Smith, Deborah A. Repert, Larry B. Barber, Denis R. LeBlanc
Potential For Denitrification near Reclaimed Water Application Sites in Orange County, Florida, 2009
The potential for denitrification was tested in water samples from four Upper Floridan aquifer wells near a reclaimed water application site, in west Orange County Florida, and two adjacent springs. Results of the study indicate that denitrifying bacteria are present in the groundwater and spring water samples, and that these bacteria can readily denitrify the waters when suitable geochemical cond
Authors
Michael J. Byrne, Richard L. Smith, Deborah A. Repert
Groundwater-quality data for a treated-wastewater plume near the Massachusetts Military Reservation, Ashumet Valley, Cape Cod, Massachusetts, 2006-08
A plume of contaminated groundwater extends from former disposal beds at the Massachusetts Military Reservation's wastewater-treatment plant toward Ashumet Pond, coastal ponds, and Vineyard Sound, Cape Cod, Massachusetts. Treated sewage-derived wastewater was discharged to the rapid-infiltration beds for nearly 60 years before the disposal site was moved to a different location in December 1995. W
Authors
Jennifer G. Savoie, Denis R. LeBlanc, Gillian M. Fairchild, Richard L. Smith, Douglas B. Kent, Larry B. Barber, Deborah A. Repert, Charles P. Hart, Steffanie H. Keefe, Luke A. Parsons
Effects of the antimicrobial sulfamethoxazole on groundwater bacterial enrichment
The effects of “trace” (environmentally relevant) concentrations of the antimicrobial agent sulfamethoxazole (SMX) on the growth, nitrate reduction activity, and bacterial composition of an enrichment culture prepared with groundwater from a pristine zone of a sandy drinking-water aquifer on Cape Cod, MA, were assessed by laboratory incubations. When the enrichments were grown under heterotrophic
Authors
Jennifer C. Underwood, Ronald W. Harvey, David W. Metge, Deborah A. Repert, Laura K. Baumgartner, Richard L. Smith, Timberly M. Roane, Larry B. Barber
Nitrification and denitrification in a midwestern stream containing high nitrate: In situ assessment using tracers in dome-shaped incubation chambers
The extent to which in-stream processes alter or remove nutrient loads in agriculturally impacted streams is critically important to watershed function and the delivery of those loads to coastal waters. In this study, patch-scale rates of in-stream benthic processes were determined using large volume, open-bottom benthic incubation chambers in a nitrate-rich, first to third order stream draining a
Authors
R. L. Smith, J.K. Böhlke, D.A. Repert, C.P. Hart
Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming
Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points range
Authors
Richard L. Smith, Deborah A. Repert, Charles P. Hart
Long-term natural attenuation of carbon and nitrogen within a groundwater plume after removal of the treated wastewater source
Disposal of treated wastewater for more than 60 years onto infiltration beds on Cape Cod, Massachusetts produced a groundwater contaminant plume greater than 6 km long in a surficial sand and gravel aquifer. In December 1995 the wastewater disposal ceased. A long-term, continuous study was conducted to characterize the post-cessation attenuation of the plume from the source to 0.6 km downgradient.
Authors
D.A. Repert, L. B. Barber, K.M. Hess, S.H. Keefe, D.B. Kent, D.R. LeBlanc, R. L. Smith
Assessment of nitrification potential in ground water using short term, single-well injection experiments
Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 μM)
Authors
R. L. Smith, L.K. Baumgartner, D.N. Miller, D.A. Repert, J.K. Böhlke
Small-scale, hydrogen-oxidizing-denitrifying bioreactor for treatment of nitrate-contaminated drinking water
Nitrate removal by hydrogen-coupled denitrification was examined using flow-through, packed-bed bioreactors to develop a small-scale, cost effective system for treating nitrate-contaminated drinking-water supplies. Nitrate removal was accomplished using a Rhodocyclus sp., strain HOD 5, isolated from a sole-source drinking-water aquifer. The autotrophic capacity of the purple non-sulfur photosynthe
Authors
R. L. Smith, S.P. Buckwalter, D.A. Repert, D.N. Miller
Allocation of extracellular enzymatic activity in relation to litter composition, N deposition, and mass loss
Decomposition of plant material is a complex process that requires interaction among a diversity of microorganisms whose presence and activity is subject to regulation by a wide range of environmental factors. Analysis of extracellular enzyme activity (EEA) provides a way to relate the functional organization of microdecomposer communities to environmental variables. In this study, we examined EEA
Authors
R. L. Sinsabaugh, M.M. Carreiro, D.A. Repert
Science and Products
Filter Total Items: 15
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inor
Natural gradient, lakebed tracer tests using nitrite in a nitrate-contaminated groundwater discharge zone in Ashumet Pond, Massachusetts
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inor
Water and Sediment Geochemistry Data from the Vicinity of Yellow Pine, Idaho, 2014-2015
Samples were collected at or near baseflow conditions. Water pH and specific conductance were measured in the field, with specific conductance also measured in the laboratory and calculated based on the ionic strength of samples based on laboratory analyses. Water samples were collected for laboratory analyses using a peristaltic pump with silicon tubing. Samples were filtered through a reusabl
Filter Total Items: 22
Long-term groundwater contamination after source removal—The role of sorbed carbon and nitrogen on the rate of reoxygenation of a treated-wastewater plume on Cape Cod, MA, USA
The consequences of groundwater contamination can remain long after a contaminant source has been removed. Documentation of natural aquifer recoveries and empirical tools to predict recovery time frames and associated geochemical changes are generally lacking. This study characterized the long-term natural attenuation of a groundwater contaminant plume in a sand and gravel aquifer on Cape Cod, Mas
Authors
Richard L. Smith, Deborah A. Repert, Larry B. Barber, Denis R. LeBlanc
Potential For Denitrification near Reclaimed Water Application Sites in Orange County, Florida, 2009
The potential for denitrification was tested in water samples from four Upper Floridan aquifer wells near a reclaimed water application site, in west Orange County Florida, and two adjacent springs. Results of the study indicate that denitrifying bacteria are present in the groundwater and spring water samples, and that these bacteria can readily denitrify the waters when suitable geochemical cond
Authors
Michael J. Byrne, Richard L. Smith, Deborah A. Repert
Groundwater-quality data for a treated-wastewater plume near the Massachusetts Military Reservation, Ashumet Valley, Cape Cod, Massachusetts, 2006-08
A plume of contaminated groundwater extends from former disposal beds at the Massachusetts Military Reservation's wastewater-treatment plant toward Ashumet Pond, coastal ponds, and Vineyard Sound, Cape Cod, Massachusetts. Treated sewage-derived wastewater was discharged to the rapid-infiltration beds for nearly 60 years before the disposal site was moved to a different location in December 1995. W
Authors
Jennifer G. Savoie, Denis R. LeBlanc, Gillian M. Fairchild, Richard L. Smith, Douglas B. Kent, Larry B. Barber, Deborah A. Repert, Charles P. Hart, Steffanie H. Keefe, Luke A. Parsons
Effects of the antimicrobial sulfamethoxazole on groundwater bacterial enrichment
The effects of “trace” (environmentally relevant) concentrations of the antimicrobial agent sulfamethoxazole (SMX) on the growth, nitrate reduction activity, and bacterial composition of an enrichment culture prepared with groundwater from a pristine zone of a sandy drinking-water aquifer on Cape Cod, MA, were assessed by laboratory incubations. When the enrichments were grown under heterotrophic
Authors
Jennifer C. Underwood, Ronald W. Harvey, David W. Metge, Deborah A. Repert, Laura K. Baumgartner, Richard L. Smith, Timberly M. Roane, Larry B. Barber
Nitrification and denitrification in a midwestern stream containing high nitrate: In situ assessment using tracers in dome-shaped incubation chambers
The extent to which in-stream processes alter or remove nutrient loads in agriculturally impacted streams is critically important to watershed function and the delivery of those loads to coastal waters. In this study, patch-scale rates of in-stream benthic processes were determined using large volume, open-bottom benthic incubation chambers in a nitrate-rich, first to third order stream draining a
Authors
R. L. Smith, J.K. Böhlke, D.A. Repert, C.P. Hart
Geochemistry of inorganic nitrogen in waters released from coal-bed natural gas production wells in the Powder River Basin, Wyoming
Water originating from coal-bed natural gas (CBNG) production wells typically contains ammonium and is often disposed via discharge to ephemeral channels. A study conducted in the Powder River Basin, Wyoming, documented downstream changes in CBNG water composition, emphasizing nitrogen-cycling processes and the fate of ammonium. Dissolved ammonium concentrations from 19 CBNG discharge points range
Authors
Richard L. Smith, Deborah A. Repert, Charles P. Hart
Long-term natural attenuation of carbon and nitrogen within a groundwater plume after removal of the treated wastewater source
Disposal of treated wastewater for more than 60 years onto infiltration beds on Cape Cod, Massachusetts produced a groundwater contaminant plume greater than 6 km long in a surficial sand and gravel aquifer. In December 1995 the wastewater disposal ceased. A long-term, continuous study was conducted to characterize the post-cessation attenuation of the plume from the source to 0.6 km downgradient.
Authors
D.A. Repert, L. B. Barber, K.M. Hess, S.H. Keefe, D.B. Kent, D.R. LeBlanc, R. L. Smith
Assessment of nitrification potential in ground water using short term, single-well injection experiments
Nitrification was measured within a sand and gravel aquifer on Cape Cod, MA, using a series of single-well injection tests. The aquifer contained a wastewater-derived contaminant plume, the core of which was anoxic and contained ammonium. The study was conducted near the downgradient end of the ammonium zone, which was characterized by inversely trending vertical gradients of oxygen (270 to 0 μM)
Authors
R. L. Smith, L.K. Baumgartner, D.N. Miller, D.A. Repert, J.K. Böhlke
Small-scale, hydrogen-oxidizing-denitrifying bioreactor for treatment of nitrate-contaminated drinking water
Nitrate removal by hydrogen-coupled denitrification was examined using flow-through, packed-bed bioreactors to develop a small-scale, cost effective system for treating nitrate-contaminated drinking-water supplies. Nitrate removal was accomplished using a Rhodocyclus sp., strain HOD 5, isolated from a sole-source drinking-water aquifer. The autotrophic capacity of the purple non-sulfur photosynthe
Authors
R. L. Smith, S.P. Buckwalter, D.A. Repert, D.N. Miller
Allocation of extracellular enzymatic activity in relation to litter composition, N deposition, and mass loss
Decomposition of plant material is a complex process that requires interaction among a diversity of microorganisms whose presence and activity is subject to regulation by a wide range of environmental factors. Analysis of extracellular enzyme activity (EEA) provides a way to relate the functional organization of microdecomposer communities to environmental variables. In this study, we examined EEA
Authors
R. L. Sinsabaugh, M.M. Carreiro, D.A. Repert