Four people will appear at Tsuen Wan Court today on charges of conspiring to defraud the Housing Authority in connection with alleged substandard piling at a Tung Chung site. Chan Fuk-chai, 36, and Mak Yiu-luen, 42, site agent and site foreman of Phone Lee Piling Construction Company respectively, Ho Hon-wai, 27, former truck driver of Castco Testing Centre, and Wu Yam-kuen, 37, former principal technician of Fugro Geotechnical Services (HK) were charged by the ICAC.