Bioremediation: The current and the future Graeme Paton Technical Director, Remedios Diarmuid O’Sullivan Senior Environmental Consultant

Bioremediation “ The act of stimulating the metabolism or co-metabolism of contaminants in the natural environment. Can be ex-situ, in-situ or involve natural attenuation” 6 months - 3 years (ex-situ usually quicker)

Decomposition of biopolymers Cell Oxidation Endoenzyme Exoenzyme Dimers Monomers Endoenzyme Exoenzyme Extracellular enzymes ?? ½ O 2 H2OH2O CO 2

Tool Kit

Induction Catabolic biosensors enable a prediction of the bioavailability of the target molecule in that matrix Hence if the genes for degradation are in the matrix, degradation is very likely

Tool Kit

Procedure for lux-based assay % of the control luminescence 100 % 10 % Increasing toxicity

Tool Kit

Paton et al 2003 MPN- Tetrazolium

Site Location- Oil spill 1

ToxicityToxicity mpnmpn InductionInduction TPHTPH Tool Kit- at oil spill

Kuwait Oil Lake- Oil spill 2 During the first Gulf war ( ) 50 million tonnes of soil was contaminated Air-borne oily material contaminated one thousand square kilometres of soil.

Systematic Grid

Can we predict? Bioremediation (f) [TPH] (f) availability (f) degraders (f) constraints BF= Induction x [TPH] mpn x (1-EC)

Prediction Once all of the data have been integrated an estimation of the likely case for degradation can be made Iroegbu et al., 2003

TPH Week 0Week 15

Prediction v Actual

Prediction There is a close relationship between the predicted value and the actual hydrocarbon concentration. This could define the end-point Regular monitoring confirmed the progress of this work This has been extended to over twenty trials to assess the value of the data

Max specific deg rate mg TPH/ day Bioremediation Factor Prediction

Max specific deg rate mg TPH/ day Bioremediation Factor Prediction

Gaswork Site- 10,000 tonnes

Bulk chemical- 2,500 tonnes

Coupling Technologies

The Big Issues On four occasions we have been required to seed/ augment a biological treatment process. This is a growing issue and a commercial opportunity.

Bioaugmentation Agents Inoc. Source Pre-condition 1, 2, 3, 4 Substrate Remedios Nutrients SoilSolution

Examples of Data

What does this mean? Oil Technics- cfu= 10 8 ; mpn Supplier 1- cfu= 10 6 ; mpn Supplier 2- cfu= 10 6 ; mpn Supplier 3- cfu= 10 4 ; mpn Oil Technics and precondition- cfu= 10 9 ; mpn Supplier 1 and precondition- cfu= 10 8 ; mpn Supplier 2 and precondition- cfu= 10 7 ; mpn Supplier 3 and precondition- cfu= 10 5 ; mpn- 10 3

Respiration Days

Degradation TPH Days

Max specific deg rate mg TPH/ day Bioremediation Factor Prediction

Max specific deg rate mg TPH/ day Bioremediation Factor Prediction

What does this mean Augmentation is possible Steps are required to refine Immobilisation of wood is not ideal Cost issues and value of application need to be considered Need to focus and develop the skill- base