Broadly, there are 3 methods ...
Published by Arvind Kumar Mishra, Managing Director at Mangdechhu Hydroelectric Project Authority
Broadly, there are 3 methods for seepage control through foundation and also within body. a) Permeation Grouting
b) Jet Grouting
c) Cut-off Wall
You have to ascertain the homogenity of the material i.e. gradation analysis. Also find out silt content and if silt is more than 18% then permeation grouting may not be effective. Find out the depth upto which grouting is to be carried out. Most effective method in the Hetrogenious mass is the Jet Grouting. If economics is allowing you, then go for cut-off wall. I have done Cut-off wall (Plastic concrete) through m/s Bauer, Germany. My email id is md.mhpa@gmail.com
AK Mishra