Appendix A: Contaminant analysis - Water Injection/Plough Dredging and Bed Levelling

Contaminant Analysis Required for Dredging Operations in the Thames

Determinand	Detection Limit (mgkg^-1 dry weight)	Analytical Technique/Notes Note all fractions of a sample should be analysed
Organics
PAH Screen by HPLC	Total hydrocarbons <100 See notes	Initial screen, if hydrocarbon contamination present further analysis would be necessary for individual PAHs.
PCBs – ICES 7 Congeners	<0.02>	If PCB contamination identified further analysis for individual congeners may be necessary.
Heavy Metals Total metals should be analysed unless stated
Arsenic	<7
Cadmium	<0.4
Chromium	<40
Lead	<30
Mercury	<0.1
Copper	<18
Nickel
Zinc	<124>
Organo-metallic Compounds
Tri-butyl Tin & Di-butyl Tin	<0.1
Physical Properties
PSD (particle size)	Gravel, sand, silt fractions