Dave Harper
Science and Products
Science Team about Energy and Plains and Potholes Environments (STEPPE)
Brine Contamination to Plains and Potholes Environments from Energy Development in the Williston Basin
The thermal regime and species composition of fish and invertebrates in Kelly Warm Spring, Grand Teton National Park, Wyoming
We evaluated the thermal regime and relative abundance of native and nonnative fish and invertebrates within Kelly Warm Spring and Savage Ditch, Grand Teton National Park, Wyoming. Water temperatures within the system remained relatively warm year-round with mean temperatures >20 °C near the spring source and >5 °C approximately 2 km...
Harper, David; Farag, AidaEnvironmental signatures and effects of an oil and gas wastewater spill in the Williston Basin, North Dakota
Wastewaters from oil and gas development pose largely unknown risks to environmental resources. In January 2015, 11.4 M L (million liters) of wastewater (300 g/L TDS) from oil production in the Williston Basin was reported to have leaked from a pipeline, spilling into Blacktail Creek, North Dakota. Geochemical and biological samples...
Cozzarelli, Isabelle M.; Skalak, Katherine; Kent, D.B.; Engle, Mark A.; Benthem, Adam J.; Mumford, Adam; Haase, Karl B.; Farag, Aïda M.; Harper, David; Nagel, S. C.; Iwanowicz, Luke R.; Orem, William H.; Akob, Denise M.; Jaeschke, Jeanne B.; Galloway, Joel M.; Kohler, Matthias; Stoliker, Deborah L.; Jolly, Glenn D.Integrated risk and recovery monitoring of ecosystem restorations on contaminated sites
Ecological restorations of contaminated sites balance the human and ecological risks of residual contamination with the benefits of ecological recovery and the return of lost ecological function and ecosystem services. Risk and recovery are interrelated dynamic conditions, changing as remediation and restoration activities progress through...
Hooper, Michael J.; Glomb, Stephen J.; Harper, David; Hoelzle, Timothy B.; McIntosh, Lisa M.; Mulligan, David R.Ecological risks of shale oil and gas development to wildlife, aquatic resources and their habitats
Technological advances in hydraulic fracturing and horizontal drilling have led to the exploration and exploitation of shale oil and gas both nationally and internationally. Extensive development of shale resources has occurred within the United States over the past decade, yet full build out is not expected to occur for years. Moreover, countries...
Brittingham, Margaret C.; Maloney, Kelly O.; Farag, Aïda M.; Harper, David D.; Bowen, Zachary H.In situ and laboratory toxicity of coalbed natural gas produced waters with elevated sodium bicarbonate
Some tributaries in the Powder River Structural Basin, USA, were historically ephemeral, but now contain water year round as a result of discharge of coalbed natural gas (CBNG)-produced waters. This presented the opportunity to study field sites with 100% effluent water with elevated concentrations of sodium bicarbonate. In situ experiments,...
Farag, Aïda M.; Harper, David D.; Skaar, DonA review of environmental impacts of salts from produced waters on aquatic resources
Salts are frequently a major constituent of waste waters produced during oil and gas production. These produced waters or brines must be treated and/or disposed and provide a daily challenge for operators and resource managers. Some elements of salts are regulated with water quality criteria established for the protection of aquatic wildlife, e.g...
Farag, Aïda M.; Harper, David D.The chronic toxicity of sodium bicarbonate, a major component of coal bed natural gas produced waters
Sodium bicarbonate (NaHCO3) is the principal salt in coal bed natural gas produced water from the Powder River Structural Basin, Wyoming, USA, and concentrations of up to 3000 mg NaHCO3/L have been documented at some locations. No adequate studies have been performed to assess the chronic effects of NaHCO3 exposure. The present study was initiated...
Farag, Aïda M.; Harper, David D.Acute toxicity of sodium bicarbonate, a major component of coal bed natural gas produced waters, to 13 aquatic species as defined in the laboratory
Water produced during coal bed natural gas (CBNG) extraction in the Powder River Structural Basin of Wyoming and Montana (USA) may contain concentrations of sodium bicarbonate (NaHCO3) of more than 3000 mg/L. The authors evaluated the acute toxicity of NaHCO3, also expressed as bicarbonate (HCO3−), to 13 aquatic organisms. Of the 13 species tested...
Harper, David D.; Farag, Aïda M.; Skaar, DonMercury and selenium concentrations in biofilm, macroinvertebrates, and fish collected in the Yankee Fork of the Salmon River, Idaho, USA, and their potential effects on fish health
The Yankee Fork is a large tributary of the Salmon River located in central Idaho, USA, with an extensive history of placer and dredge-mining activities. Concentrations of selenium (Se) and mercury (Hg) in various aquatic trophic levels were measured in the Yankee Fork during 2001 and 2002. Various measurements of fish health were also performed....
Rhea, Darren T.; Farag, Aïda M.; Harper, David D.; McConnell, Elizabeth; Brumbaugh, William G.The potential effects of sodium bicarbonate, a major constituent from coalbed natural gas production, on aquatic life
The production water from coalbed natural gas (CBNG) extraction contains many constituents. The U.S. Environmental Protection Agency has established aquatic life criteria for some of these constituents, and it is therefore possible to evaluate their risk to aquatic life. However, of the major ions associated with produced waters, chloride is the...
Farag, Aïda M.; Harper, David D.Effects of acclimation on the toxicity of stream water contaminated with zinc and cadmium to juvenile cutthroat trout
We investigated the influence of acclimation on results of in situ bioassays with cutthroat trout in metal-contaminated streams. Cutthroat trout (Oncorhynchus clarki) were held for 21 days (1) in live containers at a reference or "clean" site having dissolved metals near detection limits (0.01 ??g/L cadmium [Cd] and 2.8 ??g/L zinc [Zn]; hardness...
Harper, D.D.; Farag, A.M.; Brumbaugh, W.G.Concentrations of metals in water, sediment, biofilm, benthic macroinvertebrates, and fish in the Boulder River watershed, Montana, and the role of colloids in metal uptake
To characterize the partitioning of metals in a stream ecosystem, concentrations of trace metals including As, Cd, Cu, Pb, and Zn were measured in water, colloids, sediment, biofilm (also referred to as aufwuchs), macroinvertebrates, and fish collected from the Boulder River watershed, Montana. Median concentrations of Cd, Cu, and Zn in water...
Farag, Aida; Nimick, David A.; Kimball, Briant A.; Church, Stanley E.; Harper, David D.; Brumbaugh, William G.