Jayachandran:

You may find this link useful:

http://www.academia.edu/3784854/Sediment_Quality_Assessment_in_a_Tropical_Estuary_the_case_of_Cear%C3%A1_River_Northeastern_Brazil

Best

Syed

You can try potential ecological risk index. A publication by Robin et all

, 2011 for Cochin estuary may be referred for details.

You can also have a look at Pamela Hallock's FoRAM index. It is not a sediment but water quality index, but could be useful too.

See link and references cited in.

Cheers

http://www.icrs2012.com/proceedings/manuscripts/ICRS2012_15F_2.pdf