Total petroleum hydrocarbons bioremediation

The PetroClean bioremediation system treats biodegradable contaminants (i.e., gasoline, diesel fuel, aviation fuel, solvents, polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), semivolatile organic compounds (SVOCs), total petroleum hydrocarbons (TPH), and other organic compounds in soils and groundwater. 

Natural attenuation, often called intrinsic remediation, intrinsic bioremediation, bioattenuation, or monitored natural attenuation (MNA) is an in situ treatment technology for soil, sediment, or groundwater. The technology has been used for full-scale remediation of sites contaminated with volatile organic compounds (VOCs), total petroleum hydrocarbons (TPH), chlorinated solvents, explosives, inorganics, and metals. 

The SBP slurry-phase bioremediation system can treat a wide range of organic contamination, especially wood-preserving wastes and solvents. A modified version can also treat polynuclear aromatic hydrocarbons (PAHs) such as creosote and coal tar pentachlorophenol (PCP) total petroleum hydrocarbons (TPH) and chlorinated aliphatics, such as trichloroethene (TCE). The technology can be combined with SBP s membrane filtration system to form a soil cleaning system to handle residuals and contaminated liquids. 

Solid-phase bioremediation is an ex situ treatment technology for soil and sediment contaminated with total petroleum hydrocarbons (TPH), polynuclear aromatic hydrocarbons (PAHs), and phenols, including pentachlorophenol (PCP). 

In the selection of a microbial system and bioremediation method, some examination of the degradation pathway is necessary. At a minimum, the final degradation products must be tested for toxicity and other regulatory demands for closure. Recent advances in the study of microbial metabolism of xenobiotics have identified potentially toxic intermediate products (Singleton, 1994). A regulatory agency sets treatment objectives for site remediation, and process analysis must determine whether bioremediation can meet these site objectives. Specific treatment objectives for some individual compounds have been established. In other cases total petroleum hydrocarbons total benzene, toluene, ethyl benzene, and xylene (BTEX) or total polynuclear aromatics objectives are set, while in yet others, a toxicology risk assessment must be performed. 

Biodegradation can be accelerated in a prepared bed reactor with forced aeration. These reactors (Figure 1.2) are used at many Superfund sites for bioremediation of PAHs and BTEX (benzene, toluene, ethylbenzene, and xylene) (Alexander, 1994). This method, with recirculating leachate, was used to reduce the average total petroleum hydrocarbon concentration in a diesel-contaminated soil from 6200 mg/kg dry soil to 280 mg/kg in approximately 7 weeks (Reynolds et al., 1994). A bed reactor with forced aeration was also used to treat 115 000 m3 of soil contaminated with bunker C fuel oil (Compeau, Mahaffey Patras, 1991) and 23 000 m3 of soil contaminated with gasoline and fuel oil (Block, Clark Bishop, 1990). 

A common problem at public utilities is soil that becomes contaminated with PCBs near and around transformers. There still are a number of such sites with this problem in the United States. Table 9 gives data from a soil cleanup project from a site in New York State. The soil contained approximately 1200 ppm of PCB (Aroclor 1260) prior to treatment with SET . After treatment, the PCB level was reduced to 1.4 ppm (Table 9). Aroclor 1260 is particularly hard to bioremediate, so this result is significant. Small quantities of PAHs (pyrene and phenanthrene) were also remediated. The total petroleum hydrocarbons increased, which is what should be expected because the initial... 

Pollard SJT, Hmdey SE, Eredorak PM. (1994). Bioremediation of petroleum and creosote-contaminated soils A review of constraints. Waste Management Research 12 173-194. Potter TL, Simmons KE. (1998). Composition of petroleum mixtures. In Total Petroleum Hydrocarbon Criteria Working Group Series, Vol. 2. Amherst, MA Scientific Pnbhshers Amherst. 

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