Fall 2017 Seminar Series

This seminar series http://cuere.umbc.edu/seminar-series/ is free and open to the public.

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Parking policy

Parking passes for off-campus guests in the TRC lot are required at the cost of $4.00 per car.  Parking passes may be picked up and paid for (cash only) before seminar by stopping by the CUERE office in TRC 102 /105 and seeing a staff member.  Please contact us at 410-455-1763 with any questions regarding logistics.  

View our web site at  http://cuere.umbc.edu

Advective porewater movement, dispersion and molecular diffusion are important factors affecting the mass transfer of hydrophobic organic compounds (HOCs) in marsh and mudflat sediments. Heat transfer theory can be used to quantify porewater movement within sediment based on inexpensive and reliable temperature measurements. This approach is demonstrated for a case study site at Hunters Point Naval shipyard in San Francisco Bay, where temperature was used as a tracer, and heat transport was analysed using 14-day data from multi-depth sediment temperature logging stations with the help of a one-dimensional heat transport simulation. The best-fit conditions gave an average Darcy velocity of 3.8 cm/d in the downward vertical direction for sorbent-amended sediment with a plausible range of 0 cm/d to 8 cm/d. In a limiting case with no net advection, the best-fit depth-averaged mechanical dispersion coefficient was 2.2 × 10⁻⁷ m²/s with a range of 0.9 × 10⁻⁷ m²/s to 5.6 × 10⁻⁷ m²/s. The advective flow and/or mechanical dispersion at the test site would benefit the stabilization effect of heterogeneously distributed sorbent materials by acting to smooth out the heterogeneities and homogenizing pollutant concentrations across the entire bioactive zone. These measurements and modelling techniques on intertidal sediment porewater transport could be useful for the development of more reliable mass transfer models for the prediction of contaminant  and nutrient release within the sediment bed, the movement of chemicals in the intertidal aquatic environment, and in situ sequestration of sediment contaminants by sorbent addition.