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Bio - Remediation. Defintion. Environmental cleanup with biological agents: the use of biological methods to restore contaminated land; the addition of bacteria and other organisms that consume or neutralize contaminants in the soil. Techniques. Phytoremediation Bioventing Bioleaching
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Defintion • Environmental cleanup with biological agents: the use of biological methods to restore contaminated land; the addition of bacteria and other organisms that consume or neutralize contaminants in the soil
Techniques • Phytoremediation • Bioventing • Bioleaching • Land Farming • Composting • Bioaugmentation • Biostimulation • Mycoremediation Using gram positive microbes
Currently $6-8 billion a year is spent on environmental clean up, and $25-50 billion per year worldwide (Glass 1999; Tsao 2003) • Minerals and microbe stim http://elements.geoscienceworld.org/content/8/2/95.full
Mycoremediation and Fecal Coliform Thomas et al., (2009) • Fungal mycelium grown in straw/wood chips, demonstrated that the fecal coliform concentration of waste produced from horse pasture runoff was reduced by 50% before the effluent was transported by natural waters to commercial shellfish-growing beaches. • During the Phase 1 experiment, the fecal coliform concentrations were reduced from a mean of 30 CFU/100 ml in the inflow to 3 CFU/100 ml in the mycoremediation (treatment) cell outflow • Field Demonstrations of Mycoremediation for Removal of Fecal Coliform Bacteria and Nutrients in the Dungeness Watershed, Washington. Battelle Memorial Institute (Battelle)
Myco Remediation Cont’d • http://www.fungi.com/blog/items/the-petroleum-problem.html
Phytoremediation • Rhizofiltration - using hydroponically cultivated plant roots to remediate water through absorption, concentration, and precipitation of pollutants in aquatic environments • Some plants evolved this for defense mechanism for predators. • heavy metals are not retained in the roots but are translocated to the shoot and accumulated in above-ground organs, especially leaves, at concentrations 100–1000-fold higher than those found in non-hyperaccumulating species Rascioa &, Izzob (2011) • Treated plating effluents range from 2-5mg/L Cd, but using peat columns, the effluent could be lowered to less than 3ug/L Cd (no greater than domestic wastewater). • Could be added to soil mixtures • Hyper accumulating plants tolerate very high concentrations of organic and inorgain compounds, most commonly Zn or Ni, but also organics such as TNT (Brady & Weil 2010).
Phyto-myco combo • Mychorizal relations ship with roots to help nutrient/contaminant (only with transplants)
Phyto Cont’d • Enhanced Rhizosphere phytoremediation-plants don’t take up toxins, they release soil carbon compounds that serve as microbial growth subrtrates for growth regulation (Brady & Weil 2010).
Hyper-accumulating plants • Alfalfa • Thlaspi • Sunflowers • Rapeseed • Indian mustard greens • Duck weed • hemp • Cost comparison of bio rem strategies(Pilon-Smits & Freeman, 2006) • Some have 20000 mg/kg nickle, 40000 mg/kg Zn and 1000 mg/kg Cd
Peat could be northern Minnesota's newest cash crop • Minnesota has millions of acres of peatlands. Companies have permits to dig on only about 3,000 of those acres • Peat production in Minnesota is a $10 million dollar industry. • Companies drain the wetland and remove the top layer of vegetation. Then machines are used to either shave or vacuum the peat. Companies harvest only an inch or two of peat each year. They'll spend decades mining the same small plot. They're required to restore it when they're done. • Chaney & Hundemann (1979) also showed that peat can filter out cadmium from simulated hypochlorite-oxidized cadmium cyanide electroplating waste waters. Treated plating effluents range from 2-5mg/L Cd, but using peat columns, the effluent could be lowered to less than 3ug/L Cd (no greater than domestic wastewater)
Composting • Green waste • Need a catalyzer • Biochar • Add rock dust to stimulate microbes • Optiman C:N ratio is 30:1. Microbial growth stops if ratio is greater, and if less, N is lost as ammonia, sterns plant biology
Bio-venting • Microbes feeding off of oxygen • Bonardi et al. (2006) found forced aeration/oxygenation on coastal environments was effective in reducing heavy metals in surficial bottom sediments ( top 5-6cm), in highly polluted industrial harbours; bottom sediment plays an important mixing role in the reduction of heavy metal content. • http://www.cpeo.org/techtree/ttdescript/bioven.htm (venting in general) • http://www.jstor.org.libproxy.stcloudstate.edu/stable/10.2307/2664414?Search=yes&resultItemClick=true&searchText=bioventing&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3Dbioventing%26amp%3Bacc%3Don%26amp%3Bwc%3Don%26amp%3Bfc%3Doff (oil n venting) • Used for fuel residuals or VOCs, • Doesn’t work with chlorine • Depends on permeability of soil and biodegradability of pollutant
Sources • Bonardi, M., Ravagnan, G., Morucchio, C., Tosi, L., P. Almeida and S. De SanctisEnvironmental Recovery of Coastal Areas: The Bio - Remediation Study Case of the Industrial Harbour of Marghera, Venice, Italy.. Journal of Coastal Research , Special Issue No. 39. Proceedings of the 8th International Coastal Symposium (ICS 2004), Vol. II (Winter 2006) , pp. 1044-1048 • Chaney, R. L., and Hundemann, P. T. (1979). Use of Peat Moss Columns to Remove Cadmium from Wastewaters . Journal of Water Pollution Control Federation, Vol. 51, No. 1, pp. 17-21 • Elizabeth A. H. Pilon-Smits and John L. Freeman. Environmental Cleanup Using Plants: Biotechnological Advances and Ecological Considerations. Frontiers in Ecology and the Environment, Vol. 4, No. 4 (May, 2006), pp. 203-210 • Rascioa, N., Izzob, F. N. (2011). Heavy metal hyperaccumulating plants: How and why do they do it? And what makes them so interesting? Volume 180, Issue 2, Pages 169–181. http://dx.doi.org/10.1016/j.plantsci.2010.08.016 • http://news.minnesota.publicradio.org/features/2004/01/14_robertsont_peat/?refid=0 • Brady, N. C., Weil, R R., (2010). Elements of the Nature and Properties of Soils (3rd ed). Upper Saddle River, New Jersey: Prentice Hall. • Thomas, S. A., Aston, L. M., Woodruff, D. L., Cullinan, V. I. (2009)Field Demonstrations of Mycoremediation for Removal of Fecal Coliform Bacteria and Nutrients in the Dungeness Watershed, Washington. Battelle Memorial Institute (Battelle): http://dungenessrivercenter.org/documents/FinalMycoremediationReport_000.pdf