Tailings Dam – Qianxi, Hebei

This valley-type tailings facility in Qianxi, Hebei, uses a permeable rock-fill starter embankment with an upstream storage embankment built by compacting coarse sand from the reservoir area. Originally designed with a crest elevation of 212 m, a total dam height of 58.4 m and a storage capacity of 2.104 million m³ as a Grade IV facility, it was upgraded after a 2010 technical-modification design to Grade III, adding 3.779 million m³ of capacity. Because the dam lies adjacent to a river reservoir, failure would cause severe and lasting environmental impact, so an online monitoring system is essential to track its safety.