Research on Inpit Dumping Height during Tracing Mining Period between Two Adjacent Surface Coal Mines

Table 3

Secondary stripping amount and the cost with 1100 elevation dumped of Heidaigou surface coal mine.

Year	Secondary stripping tonnage (m^3 × 10^6)	Stripping unit price (yuan)	Secondary striping cost (million yuan)
2015	3.78.	12	4.54
2016	30.72	12	36.87
2017	33.68	12	40.42
Total	68.19	12	81.83