The NPD mndandanda chitoliro jacking makina makamaka oyenera mikhalidwe geological ndi kuthamanga kwa madzi pansi ndi mkulu permeability coefficient nthaka. Slag yofukulidwa imatulutsidwa mumsewu ngati matope kudzera pampope yamatope, kotero imakhala ndi makhalidwe abwino kwambiri ogwira ntchito komanso malo ogwirira ntchito.