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1.1 Research Projects
Please update your project information on this page. We will use the information here to populate the research project pages on the lab website: hydro-lab.
The transboundary Limpopo River Basin crosses Botswana, Zimbabwe, South Africa, and Mozambique. At over 400,000 km^2, the Limpopo Basin is home to 18 million people living in both rural and urban areas. Industries in the Basin include businesses in the urban areas and water-intensive uses such as agriculture and mining; industrial water use is growing rapidly. In addition to the human residents, the Basin contains some of the most biodiverse natural areas on the planet including Kruger National Park and the UNESCO Vhembe Biosphere Reserve.
The Satellite River Gage project develops a relationship between width as measured by satellites with river discharge.
Groundwater measurements by GRACE satellite.
This work is supported through the WaterQ2: Understanding Water Quality and Quantity in the Limpopo Basin program through a generous grant from the United States Agency for International Development.
We are involved in research with the Pure Thirst group at Duquesne. Pure Thirst and our research are focused on a rural mountain community in northern Tanzania. Key water issues that face the residents are:
- Microbial pathogens
- Excess fluoride from the geothermal area
- Aging distribution system
- Water infrastructure availability in key areas: the school and the clinic
This work is supported by the Loogman Faculty Research Grant, Paluse Faculty Research Grant, Bayer School of Natural and Environmental Sciences Office of the Dean, School of Nursing, and the Honors College.
Groundwater is a critical resource as the largest reservoir of liquid fresh water. Water systems that supply approximately one-third of customers in the U.S. and 98% household well withdrawals depend on safe groundwater. Unfortunately, groundwater is vulnerable to contamination by a large range of hazardous materials. Remediation of these contaminants is needed to return the aquifer to a usable condition; however, these efforts are lengthy and expensive.
The most common method is pump-and-treat either alone or in conjunction with another technology. This approach uses pumps to remove contaminated water from an aquifer. One major bottleneck to remediation is that contaminants become trapped in pores that do not have a flow into and out of the pore; these pores have a dead end and thus are termed dead-end pores. Contaminants in these dead-end pores can remain in groundwater despite extensive treatment and release contaminant back into the aquifer after treatment.
The US Environmental Protection Agency identified a serious and common problem in pump-and-treat remediation sites: after remediation ends and without external sources, contaminant levels in the aquifer rise again to unacceptable levels; this is known as rebound. There are several categories of sources for contaminant; however, the current work here focuses on matrix diffusion from dead-end pores. The only way that contaminant leaves dead-end pores is by diffusion. Rebound can pose a serious health risk to those who rely on the aquifer for water supply and will inevitably result in an expensive redeployment of remediation equipment.
Numerical and laboratory experiments confirm that sudden changes in flow rate can alter the fluid dynamics into and around these pores and improve contaminant removal. Rapidly pulsed flow (with a period on the order of one second) achieves significantly better contaminant removal than steady flow. These processes have not yet been fully exploited in groundwater remediation. Implementation of rapidly pulsed technology would utilize the same extraction and injection wells currently used in pump-and-treat remediation but could require replacement or modification of the pumps. Further research into this will include large-scale testing of rapidly pulsed pumping and improvements to numerical models to include various sorption processes and contaminant types (e.g., NAPL).
Pittsburgh has a long history of air pollution. The COVID-19 lockdowns provided a natural experiment for air pollution. The lockdowns meant a significant reduction in commuting while certain industries did not stop.