Our research aims to improve the understanding of subsurface processes that affect soil and water quality. Our work in the following six related topics embraces the complexity of subsurface processes while still emphasizing mechanistic science.
The link between climate change and water quantity is known, but it is unclear whether and how climate change may affect water quality. Our research shows that changing weather patterns—expected during climate change—may affect contaminant transport and removal in the subsurface soil, thereby affecting water quality. Click here for details.
Adequate sources of water and energy are needed to sustain the development in urban areas— home to more than 50% of world’s population. We utilize natural systems to treat stormwater and wastewater created during energy production so that both water and energy (to treat and transport water) can be saved. Click here for details.
Increases in stormwater runoff increase erosion, flooding, and contamination of water resources. Stormwater treatment not only reduces these negative impacts but also provides a water resource for replenishing groundwater or augmenting non-potable water supply. To improve treatment of stormwater in natural systems, we develop methods based on hydrological and biogeochemical manipulation of the filter media. Click here for details.
Plant, fungi, and microbial community typically accelerate the degradation of various types of contaminants in soil, but whether they can help degrade asbestos fibers—exposure to which can cause of mesothelioma and lung cancer—in soil is unknown. We hypothesize that they can! In particular, we examine the leaching of iron, magnesium, and silica from asbestos fibers exposed to plant and fungal exudates and compare the toxicity of treated asbestos fibers with the untreated fibers. Click here for details.
Colloids are fine particles (1 nm to ~ 10 μm) that stay suspended in water. Colloids can facilitate the transport of contaminants in the subsurface soil, thereby increasing the risk of groundwater contamination. Decades of study has improved the understanding of colloid transport in a saturated soil under different geochemical conditions, but it is not clear how colloid mobilization process is affected by complex conditions in unsaturated soils. Our research examines how a transient in weather conditions affects the physical, geochemical, and biological processes responsible for colloid release in the subsurface soil. This work is particularly useful to determine whether extreme weather conditions, which become more frequent during climate change, could increase the risk associated with particulate contaminants and pathogens in surface or subsurface environments and ultimately groundwater. Click here for details.
Rainwater can dissolve contaminants from their sources on the Earth surface and convey them to groundwater and surface waters via stream and river. Transport of dissolved contaminants depends on several processes including sorption to soil minerals, transformation or degradation in water (and soil), and uptake by microorganisms. Because most of these processes may occur simultaneously in nature, it is difficult to distinguish the dominant process that removes contaminants in soil. Using batch and column experiments, we identify the competing process that affects the fate and transport of dissolved contaminants including radionuclides, heavy metals, and endocrine disrupting compounds in the subsurface soil. Click here for details.
- Prof. Joseph N Ryan, University of Colorado-Boulder
- Prof. Alexandria B Boehm, Stanford Univesity
- Prof. Jane Willenbring, University of California-San Diego (Scripps Institution of Oceanography)
- Prof. Douglas Jerolmack, University of Pennsylvania
- Prof. James E Saiers, Yale University
- Prof. Brenda Casper, University of Pennsylvania
- Prof. Kara Nelson, University of California-Berkeley
- Dr. Ronald W Harvey, United State Geological Survey (USGS)
- Dr. George Aiken, United State Geological Survey (USGS)
- Dave Metge, United State Geological Survey (USGS)
- Prof. Chittaranjan Ray, University of Nebraska-Lincoln
- Prof. Sujith Ravi, Temple University
- Dr. Keri Cantrell, United State Department of Agriculture (USDA)
- Ed Matthiesen, Wenck Associates, MN.