2005年3月22日,兰州大学生命科学院教授张正春在北京游览期间,偶然目睹了圆明园湖底铺设防渗膜这一“宏伟工程”。据后来记者目击:机器将干枯的湖底土层翻起,再压平。工人把6米宽、50米长的大卷白色防渗膜展开后铺在湖底,再覆盖上50厘米厚的土层,然后用水泥将防渗膜与驳岸砌死 On March 22, 2005, Professor Zhang Zhengchun, a professor of Life Science at Lanzhou University, accidentally witnessed the grand project of laying a seepage prevention membrane at the bottom of Yuanmingyuan Park during his visit to Beijing. It was later witnessed by reporters: the machine will dry the bottom of the lake up, and then flatten. Workers to 6 meters wide, 50 meters long roll of white impermeable membrane spread after laying in the lake, and then covered with 50 cm thick soil, and then cement impermeable membrane and revetment to death