Pollutant fluxes to aquatic systems via bed-sediment processes
- Louisiana State Univ., Baton Rouge, LA (United States); and others
Hydrophobic organic contaminants (HOCs) sorb strongly to sediments and partition weakly into the porewater and overlying water. This leads to the detection of HOCs in sediments long after, their original introduction to the environment. Water bodies with active sediment processes have larger fluxes of HOCs to overlying water. In the absence of sediment resuspension by erosive processes, the normal life cycle activities of benthic organisms will predominate in the transport of particles from within the sediment bed to the sediment-water interface. As a result the HOCs associated with the particles are released to the water column. This process is called bioturbation and is the focus of this paper. There are a number of species that act as bioturbators. The most prevalent ones, especially in contaminated sediments across many sites in the U.S. are the Tubificidae species that burrow within the sediment and defecate at the surface. Capping with clean sediment is a possible remediation measure for isolating the aquatic system from contaminated sediments. The placement of the cap will effectively increase the pathlength for contaminant transport by diffusion and advection and, will also decrease pollutant release by direct bioturbation of contaminated particles. This paper describes our experiments on contrasting the flux of HOCs from bioturbated capped and uncapped sediments in small laboratory microcosms with those of control microcosms (capped and uncapped) without bioturbators.
- OSTI ID:
- 111510
- Report Number(s):
- CONF-9504110-; CNN: Grant R 819165-01; TRN: 95:005009-0053
- Resource Relation:
- Conference: 21. Environmental Protection Agency (EPA) annual Risk Reduction Engineering Laboratory research symposium, Cincinnati, OH (United States), 4-6 Apr 1995; Other Information: PBD: 1995; Related Information: Is Part Of 21st Annual RREL research symposium: Abstract proceedings; PB: 398 p.
- Country of Publication:
- United States
- Language:
- English
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