title: A universal nutrient application strategy for the bioremediation of oil-polluted beaches.
abstract: Biostimulation by nutrient application is a viable technology for restoring oil-contaminated beaches. Maximizing the nutrient residence time is key for achieving a rapid cost-effective cleanup. We considered the nutrient injection strategy through a perforated pipe at the high tide line and we simulated numerically beach hydraulics, which allowed us to estimate the optimal injection flow rate of nutrient solution. Our results indicate that the optimal application is one that starts following the falling high tide and lasts for half tidal cycle. The saturated wet-front of the nutrient solution on the beach surface would move seaward with the same speed of the falling tide keeping a constant distance with the tide line. The numerical results were generalized to beaches of wide ranges of hydraulic and tidal properties using a novel dimensionless formulation for water flow and solute transport in porous media. Nomographs were presented to provide the flow rate based on four parameters: The beach slope and hydraulic conductivity, and tidal amplitude and period.
authors.affiliation: Department of Civil and Environment Engineering, Temple University, 1947 N. 12th Street, Philadelphia, PA 19122, USA. hailong@graduate.hku.hk
authors.forename: Hailong
authors.initials: H
authors.lastname: Li
authors.forename: Qinghong
authors.initials: Q
authors.lastname: Zhao
authors.forename: Michel C
authors.initials: MC
authors.lastname: Boufadel
authors.forename: Albert D
authors.initials: AD
authors.lastname: Venosa
mesh_terms: D001493:Bathing Beaches; D001673:Biodegradation, Environmental; D003198:Computer Simulation; D005308:Fertilizers; D008962:Models, Theoretical; D009584:Nitrogen / Q000378:metabolism; D010578:Petroleum / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism; D054712:Salinity; D012623:Seawater; D012988:Soil Microbiology; D014872:Water Movements; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D005308:Fertilizers; D010578:Petroleum; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen