Prof Irene M C Lo and her former PhD student, Dr. Keith C K Lai, have been selected by the Environmental Water Resource Institute of the American Society of Civil Engineers to receive the 2009 Wesley W Horner Award for their paper entitled "Effects of Seepage Velocity and Temperature on the Dechlorination of Chlorinated Aliphatic Hydrocarbons". The Award was instituted in 1968 by American Society of Civil Engineers and is made to the author(s) of the paper that makes the most valuable contribution to the environmental engineering profession. According to the record of past award recipients, Prof Lo and Dr. Lai are the second Asian researchers for 41 years to receive this Award. The Award contains a plaque, a certificate and cash prize of US$1000.