The rain will percolate through the soil.

雨水渗入土中。

《新英汉大辞典》

The heavy metal content of the remediated soil and the water quality of the percolate passing through the reactive barrier meet the corresponding national standard.

修复后土壤重金属含量以及通过反应墙渗滤液的水质符合相应的国家标准。

youdao

The water has to percolate through the soil, it's got to go through unsaturated rock, it's then got to go to the aquifer, and then it's got to be transported and discharged in the river.

BBC: Thames archive reveals long nitrate rise