In situ application of activated carbon and biochar to PCB-contaminated soil and the effects of mixing regime.
The in situ use of carbon amendments such as activated carbon (AC) and biochar to minimize the bioavailability of organic contaminants is gaining in popularity. In the first in situ experiment conducted at a Canadian PCB-contaminated Brownfield site, GAC and two types of biochar were statistically equal at reducing PCB uptake into plants. PCB concentrations in Cucurbita pepo root tissue were reduced by 74%, 72% and 64%, with the addition of 2.8% GAC, Burt's biochar and BlueLeaf biochar, respectively. A complementary greenhouse study which included a bioaccumulation study of Eisenia fetida (earthworm), found mechanically mixing carbon amendments with PCB-contaminated soil (i.e. 24 h at 30 rpm) resulted in shoot, root and worm PCB concentrations 66%, 59% and 39% lower than in the manually mixed treatments (i.e. with a spade and bucket). Therefore, studies which mechanically mix carbon amendments with contaminated soil may over-estimate the short-term potential to reduce PCB bioavailability.
Department of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, ON K7K 7B4, Canada. Electronic address: mackenzie.denyes@rmc.ca.
Mackenzie J
MJ
Denyes
Allison
A
Rutter
Barbara A
BA
Zeeb
D000818:Animals; D001673:Biodegradation, Environmental; D002606:Charcoal / Q000737:chemistry*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D009835:Oligochaeta / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism
D012987:Soil; D012989:Soil Pollutants; C540010:biochar; D002606:Charcoal; D011078:Polychlorinated Biphenyls
AC; Activated Carbon; Activated carbon; BSAF; Biochar; Biota to Sediment/Soil Accumulation Factor; CEC; Cation Exchange Capacity; GAC; Granular Activated Carbon; HOCs; Hydrophobic Organic Contaminants; In situ immobilization; MAE; Microwave Assisted Extraction; PAC; PAH; PCBs; POPs; Persistent Organic Pollutants; Phytoextraction; Polyaromatic Hydrocarbon; Polychlorinated Biphenyls; Polychlorinated biphenyls; Powdered Activated Carbon; RMC; Remediation; Royal Military College of Canada