The Applications of Chemical Analyses of Sediments and Soils in ...

IDENTIFICATIONSAttempts are made to identify a wide range of materials. Paper and thin layerchromatography procedures were previously used but are time consuming and arebeing replaced by semi-quantitative spectrographic analysis of solid samples. X-raydiffraction has also been used in co-operation with Dr. J. R. Kramer of McMaster'sUniversity, Hamilton. Of interest was the identification by X-ray diffraction of almostpure crystalline struvite (hydrated magnesium ammonium phosphate) blocking pipingat the Lakeview Sewage Treatment Plant.FUTURE DEVELOPMENTSWith increasing public awareness of environmental hazards and response bygovernment agencies, there is an increasing demand on the laboratory. The role ofsediments and soils is becoming increasingly appreciated reflected in the number ofsamples and tests. No longer is the relatively straight forward total elemental compositionanalysis sufficient but information is required on chemical species, inorganic andorganic complexes and their availability to biota. The importance of the interstitialwater and redox measurements in sediments and soils is becoming recognized and theneed to measure "free" versus "combined" metals in the aqueous phase interactingwith the sediment. The need to isolate and analyze thin layers and hence smallsamples such as at the sediment-water interface or parts of a plant or animal organshas become a challenge to the analyst.The detection limit for elements such as cadmium has to be improved by45